US1966115A - Circuit controller - Google Patents

Description

July 10, 1934- R, c. DA COSTA CIRCUIT coNTRoLLE Filed May lO, 19322 I N V EN TOAR. 5055/? /is/Z A TTORNE Y.

B'M' @im .Mw/v w R. www

Patented July 10, 1934 UNITED STATES PATENT OFFICE CIRCUIT CONTROLLER Application May 10, 1932, Serial No. 610,392

8 Claims.

This invention relates to circuit controllers, and particularly to oscillating snap switches.

It is among the objects of the invention; to provide a snap switch of cheapness and simplicity of construction while maintaining a high eciency and'long life; to reduce the number of parts formerly necessary in constructing snap switches; to provide a snap switch with contacts which engage with certain areas in physical contact to close a circuit, and which disengage with different areas in disrupted physical contact to open a circuit to minimize wear on the contacting areas; to provide a snap switch having means for securing resilient guided oscillation of a snap element, with means for positively moving the snap element for a portion of its oscillation; to provide a snap switch which automatically cleans its own contacts; to provide an improved bearing for oscillating shafts; to provide a snap switch of low series resistance; to provide a snap switch with an improved motion limiting device; to provide a simple and compact snap switch of improved character; to improve the snap mechanism in switches; and many other objects and advantages as will become more apparent as the description proceeds.

In the accompanying drawing:

Fig. 1 represents a transverse horizontal section with the parts in substantially mid position,

Fig. 2 represents a transverse vertical section partially in full lines, with the parts in one extreme position,

Figs. 3 and 4 represent fragmentary details.

The invention is illustratively disclosed as embodied in a small compact unit suitable for use in radio sets and the like, although obviously applicable to general circuit controlling purposes. In its preferred embodiment, at least one pair of contacts are provided in fixed relation, and the circuit is controlled by a bridge piece movable with a snap action relative to the fixed contacts.

A shell is provided comprising a bent piece of sheet metal forming an end wall 10, having a central recess or depression l1, a side Wall 12 having a bearing opening 26, and an end wall 13, which all may be formed by a stamping. The free ends of the end walls and 13 are secured in anchoring wall 14 which may carry integral tabs or anchoring ends 15 by which the unit may be secured in a desired location. Anchoring Wall 14 has a semi-cylindrical opening 16, opposite to and in registration with the bearing opening 26 in the opposite side wall l2. The' respective openings are relatively close to end Wall 13. Partially cylindrical opening 16 contains a V-shape tongue (Cl. 20D-68) 17 formed, preferably, integrally with the anchor wall 14. 'In the form disclosed the V or wedge shaped tongue is substantially a sector of the opening 16, and has a terminal tip 18 substantially at the axis of the opening. The sector tongue 17 is illustrated as forming a little less than 90 of the opening 16, although as will be pointed out the arcuate extent of the tongue may be varied in accordance with the limitations desired upon the oscillations of the associated shank to be described. It will be noted that the respective edge faces 7 and 8 of the tongue 17 form stops for the associated shank.

A sheet of insulating material 20, may be provided as a lining of the shell. The open sides of the shell are closed byrigid insulating sheets or plates 21 and 22, suitably anchored to the edges of the respective walls. The plate 22 carries a pair of fixed but slightly resilient contacts 36 and 37. These contact elements may also be duplicated on plate 21 if it is desired to provide a controller for two separate circuits instead of for one circuit as illustrated.

A control piece comprised of an oscillating shank or rock-shaft 23 is provided, which may be described as partially cylindrical in that it has cylindrical surface 24 of substantially the same curvature as the opening 16, and' has a fiat side 25 extending longitudinally of the shank. The flat side 25 may be described as having two surfaces 5 and 6 merging or meeting substantially on the median line of the face 25 which as illustrated is coincident with the axis of the shank. The respective surfaces 5 and 6 are arranged for engagement with the respective lstop surfaces 7 and 8 of the stop tongue 17. It will be clear that the surfaces 5 and 6 may have angular relation to each other diiferent from the 180 relation disclosed. 'I'he variation in angular surface relation and a variation in the angular relation of the stopv faces 7 and 8 of tongue 17 may be utilized to vary the degrees of oscillation permitted to the shank or shaft 23, it being understood that the shank 23 is oscillatably received in bearing opening 16. The shank extends through opening 16, and the arcuate surface 24 slidably engages the annular surface of the opening 16. The tip 18 of tongue 17 extends close to and almost touches the face 25 of the shank. A slight tolerance is advisable to permit free oscillation depending upon the accuracy of the machining. The end of shank 23 is journalled and anchored in bearing opening 26 in wall 12. Any desired operating mechanism may be mounted on the outer'qfree spring,

end of shank 23, to permit manual or other oscillation of the shank.

A guiding plate 27, having a guide groove 28, is rigidly mounted upon the flat side or face 25 of the shank, with the groove extending parallel to the face 25. The attachment may be by any desired means such as by ears 30 upset in suitable transverse slots in the surface 24. The plate has stops 31 extending outwardly in alignment with but substantially perpendicular to the groove 28.

The movable contact element or bridge comprises a substantially cylindrical insulating element 32 having an internal axial bore 33 having an internal shoulder 29, and having a tapering rounded end or nose 34 arranged for guided sliding engagement with the surface of groove 28 in plate 27. A metallic sleeve 35 is rigidly mounted on the cylindrical element 32, in position and of such diameter as to frictionally engage the spaced contacts 36 and 37 upon suitable vertical positioning of the element to an extreme position. A guide pin 38 having flange 40 has one end seated in depression or recess 1l in end wall 10, and the other end slidably disposed in bore 33 of' the insulating element 32. A helical spring 4l surrounds the pin 38 and engages between the flange 40 and shoulder 29 of the element and urges the element toward the groove in plate 27. The resilient spaced contacts 36 and 37 have each an extension 43 and 44 including terminals for attachment of suitable connecters for the circuit to be controlled.

vIt will be understood that the nose 34 of insulated element 32 is held against the guiding plate 27, in its groove 28, by pressure from helical spring 41, and normally at an end of the plate in contact with one or the other of stops 31. With the nose 34 in the end of the groove 28, it

will be observed that perpendicular stop 31 endsadjacent the rounded nose well back from the tip thereof.

It will be appreciated that with the contactor or bridge in one extreme position, oscillation of the shank causes pressure on the plate 27 to force the contacter axially toward end wall 10, on'the guide pin 38, thus compressing spring 41. Through frictional engagement of the ends of the spring, its compression4 is accompanied by relative rotative motion of the end turns of the Which imparts a twisting motion to the contact during its axial movement which effects a wiping or cleaning action upon the stationary contacts 36 and 37. This may be enhanced by causing the guiding plate to be canted a trifle, so that the rounded nose has a rotation imparted to it during its slide from one end of the plate to the other during an oscillation of the shank 23.

It will be understood that the insulating bridge element 32, guide pin 38, and coil spring 41 comprise a telescoping unit resiliently*urgecl to extended relation, and the arrangement of recess 11 relative to the axis of the shank cr rock shaft 23, lying in a plane transverse of the shell substantially medially thereof, enables the pivotal mounting of one end of the telescoping unit to swing on an axis lying substantially in said plane while the free end of the telescoping unit, the nose 34 of the element 32, is guidably disposed in the track or groove 28 of the guide plate 27. Actuation of the rock shaft imposes endwise pressure on the telescoping unit from stop 31, sliding the cylindrical bridge sleeve axially relative to the fixed contacts 36 and 37, thus wiping same, as previously noted. Owing to the change of angular position of the rock shaft and its rigid guide plate, the compressing action urging the telescopic unit to retracted relation is accompanied by the imposition of lateral pressure on nose 34 back of its tip, from the end of adjacent perpendicular stop 31, which forces the nose 34 out of the end of the groove 28 and starts or initiates its sliding movement toward the other end of the groove. This initial impetus thus positively given the snap element is accompanied by a further change of angular relation of the guide plate until the angle of the guide plate groove is such as to enable the outward urge of the spring 41 to cause the nose 34 to slide along the inclined groove to contact with the opposite stop 31, and to snap the unit on its axis in recess 11 past dead center to its opposite adjusted disposition.

It will be understood that although the first part of the snap movement is a positive movement of the snap element, yet the final part of the movement is a true resilient snap action lodging nose 34 in the pocket formed by the end of groove 28 and stop 31. The reverse snap movement, incident to an opposite oscillation of rock shaft 23 will have the same cycle of movements, namely, an initial positive movement and a final snap action. This snap operation when taken in connection with the telescopic expansible unit, provides an important advantage of this invention, in that the relation of the cylindrical bridge element 35 to the contacts B6-and 37 differs as to whether contact is being made or broken. Thus the sleeve 35 is moved axially rearwardly (toward pivot 11) relative to the iixed contacts, owing to the positive telescopingat the beginning of the circuit breaking movement, so that the sleeve separates from the contacts in a retracted position. On the reverse or circuit making movement, the retraction of the sleeve at the beginning of the movement incident to telescoping the unit is without effect relative to contacts 36 and 37 (in the single circuit control shown) as the snap to bridging circuit closing is accompanied .by an expansion of the unit so that the sleeve is advancing axially or forwardly at the instant of engaging contacts 36 and 37. This contributes to the long life of the switch.

The operation and obvious advantages of the invention are thought to be clear from the foregoing description.

I claim:

1. In circuit controllers, an oscillatable shank, a guide plate mounted on the shank and having a guiding groove, a pair of contact elements disposed in spaced parallel planes substantially parallel with the groove, a cylindrical bridge element having an axis substantially parallel with the plane of the contact elements', means on the bridge element in sliding guiding engagement with the groove, means urging said last mentioned means into engagement with the groove, 'and means for limiting the oscillations of the shank on each side of dead center of the bridge element, a metal sleeve disposed concentrically on said element in position to frictionally engage the contact elements.

2. In circuit controllers, a frame, including an element having a depression, a shank journalled on the frame with its axis substantially in alignment with the depression, a guide plate having a groove and mounted on said shank and extending perpendicularly beyond said axis, an insulating element having a tapered nose, a guide pin slidably associated with the element and engaging the depression, a spring operably associated with the element to urge it against the plate, contact means operably positioned, and a cylindrical contact element carried by the insulating element in position to bridge the contact means.

3. In snap switches, a shank, a frame, the frame having an annular opening, a segmental tongue extending into the opening, the shank having a partially annular portion disposed in the opening, and having a at surface engageable with said tongue.

4. In circuit controllers, a shell comprised of side and end walls, the side walls having substantially registering openings adjacent one end \wall, one of said openings comprising a semicylindrical opening having a wedge shaped tongue, a semi-cylindrical shank journalled in said openings and having a surface formed of merging ilat facesarranged for respective abutting engagement with sides of the wedge shaped tongue, a grooved guide plate mounted on the shank with the groove extending transversely thereof, stops on said plate at the extremities of the groove, a cylindrical `rigid element having a rounded nose engageable in said groove and against said stops and having an axial bore, a pin pivotally engaging an end wall in alignment with said shank and slidably disposed in said bore, resilient means urging the element into sliding engagement with said groove, a metallic sleeve mounted on the element, a pair of contacts arranged for frictional engagement by the sleeve when the nose of thev element abuts a stop at the end of the groove in one extreme position when one face of the shank engages a face of the wedge shaped tongue, the whole so arranged that the metallic sleeve is out of engagement with said contacts when the nose of the element abuts the other stop at the other end of said groove in the other extreme position of the shank with the other face thereof abutting the other edge of the tongue.

5. In switches, a cylindrical insulating member having a rounded nose, an axial bore and an internal shoulder, a pivoted guide pin slidable in the bore, a spring surrounding the pin and engaging the shoulder to urge the element downwardly on the pin, a metallic sleeve surrounding the member, a rock shaft, means for limiting the oscillations of the rock shaft, a guide plate mounted transversely ony the rock shaft and havin'g a groove in which the nose of said member is slidably guided, stop means at the ends of said groove, a pair of resilient contacts disposed in the path of movement of the metallic sleeve with the element upon oscillation of the rock shaft.

6. In circuit controllers, a pair of spaced resilient contacts, a bridge element movable toward and away from between said contacts, the bridge member including a concentric cylindrical metallic sleeve, and means for securing rotation of the sleeve relative to said contacts so as to clean said contacts. i

7. In snap switches, a pair of parallel spaced resilient contacts, a cylindrical bridge element, means operatively associated with the bridge element for moving it with its axis in a plane parallel to the resilient contacts to circuit making and breaking relation with a snap action, means for axially addusting said element relative to said contacts to a different position for making the circuit from its position when breaking the circuit.

8. In snap switches, a pair of parallel spaced resilient contacts, a cylindrical bridge element, means operatively associated with thebridge element for moving it with its axis in a plane parallel to the resilient contacts to circuit making 110 and breaking relation with a snap action, means for axially adjusting said element relative to said contacts to a different position for making the circuit from its position when breaking the circuit, and means for rotatably-adjusting said element during an oscillation thereof.

ROBERT C. DA COSTA.

Images