US2948793A

US2948793A - Electrical switch

Info

Publication number: US2948793A
Application number: US790715A
Authority: US
Inventors: Donald H Lanctot
Original assignee: DON LAN ELECTRONICS CO Inc
Current assignee: DON LAN ELECTRONICS CO Inc
Priority date: 1959-02-02
Filing date: 1959-02-02
Publication date: 1960-08-09
Anticipated expiration: 1977-08-09
Also published as: GB878433A

Description

Aug. 9, 1960 D. H. LANCTOT ELECTRICAL SWITCH 2 Sheets-Sheet 1 Filed Feb 2, 1959 IIII'II' IIIIIIII INVENTOR. DONALD H. LANCTOT e gmw fldz 'w Aug. 9, 1960 Filed Feb. 2, 1959 D. H. LANCTOT 2,948,793

ELECTRICAL SWITCH 2 Sheets-Sheet 2 INVENTGR. DONALD H. LANCTQT' BYQAMYQ %7&%/ ATTORNEYS ELECTRICAL swrroH Donald Lanctot, Malibu, Califi, assignor to Don-Lan Electronics Co., Inc., a corporation of California Filed Feb. 2, 1959, Ser. No. 790,715

7 Claims. or. 200- 163) This invention relates generally to electrical switches ami more particularly to manually operable miniature switches for switching high frequency electrical energy.

One of the more troublesome problems in electrical switches resides in the making or breaking of a reliable electrical contact between the conductors to be connected or disconnected. Generally, switches employ some type of contact arm including a conducting portion arranged to connect the two conductors upon movement in one direction and to disconnect the conductors upon movement in an opposite direction. In the case of switches which are subject to severe environmental conditions such. as excessive shocks and vibrations, it is very important to maintain a high contact pressure when conductors are connected together. Moreover, contact bounce and poor conductivity after prolonged use as a consequence of. dirt, grit, corrosion, and the like at the contact areas should be minimized.

Bearing the. foregoing in mind, one object of the present invention is to provide an improved electrical switch which is capable of withstanding relatively severe shocks and vibrations.

Another important object is to provide a switch in which a high contact pressure is always maintained when the switch is in its on position.

Still another object is to provide a novel switching contactv arrangement providing both the desired high contact pressure and self-cleaning action to the end that a high degree of conductivity through the switch when in its on position is maintained over an extended period of life.

More general objects of the invention are to provide miniaturized high frequency switches of compact, light weight, and economical construction.

Briefly, these as well as many other objects and advantages of this invention are attained by providing a basic casing structure having a transverse passage. Suitable input and output connectors or other conducting bodies to be connected together extend into the casing and terminate in inner ends adjacent opposite sides of the transverse passage. A single integral switching bar along the axis of the passage. a sm all ring made of highly conductive material.

of the passage and the inner contacting ends of the con ductors at their termination pointson the passage. 7

By the foregoing arrangement, movement of the.

switching bar in a given direction will cause the conducting ring to move between the inner ends of the conductors to electrically connect the same. The spacing between. the inner ends ofthese conductors is made slightly less than the outside diameter of the ring so that-upon urging of the ring between .the inner conductors, the ring itself isdistorted to asomewhat oval'shape, thereby. result-ing;

in a relatively high contactipressure;between substaru tially opposite.diametricahpoints on,the ring and the 70 ernd? the n e ns e rss veln The ring is preferably supported within a longitudinal opposite sides of ice slot in the switching bar. The inside wall surfaces of the transverse passage retain the ring within the slot and yet the ring is free to roll or move slightly within the slot. With this type of support for the ring, urging of the same between the inner ends of the conductorswill result in slight rolling movements of the ring as well' as the heretofore referred to squeezing action to distort the same and as a consequence, the contacting surfaces are self-cleaning. Moreover, as a further consequence of the intentional distortion of the'ring when in contact with the inner ends of the conductors, there is no;

possibility of contact bounce or the like and the entire structure will maintain an excellent electrical connec tion even under relatively severe shocks and vibrations.

By extending the length of the switching bar and pro.- viding additional rings, multiple pole multiple throw' switches may be provided.

A better understanding of the invention will be had. by referring to the preferred embodiments thereof as v illustrated in the accompanying drawings, in which:

Figure 1 is an overall perspective view of a first em-- bodiment of the electrical switch of this invention;

Figure 2 is an elevational cross sectional view taken in the direction of the arrows 22 of Figure 1 showing: the switching bar in its on position;

Figure 3 is a View similar to Figure 2 illustrating the switching bar in its 05 position.

Figure 4 is an enlarged fragmentary view partly in. cross section taken in the direction of the arrows 4-4- of Figure 1;

Figure 5 is an exploded perspective view of the switch-- ing bar and conducting ring portions of the switch of Figures 1, 2, and 3;

Figure 6 is a perspective view of a second embodiment: of the switch of this invention;

Figure 7 is an elevational cross sectional view taken; in the direction of the arrows 7-7 of Figure 6 showing the switching bar in a first position; and,

Figure 8 is another elevational cross sectional View similar to Figure 7 illustrating the switching bar'in' a. second position.

Referring tothe embodiment of Figure 1, there is: shown a casing 10 having an input conductor or probe 11 and a threaded co-axial connector 12 on one side; and an output conductor 13 and threaded co-axial con-- nector 14 on the opposite side. A switching bar 15 ex tends transversely through the casing 10 Within a transverse passage or bore 16 as seen in Figure 2. The ar-' rangement is such that the switching bar 15 can be manually moved back and forth within the transverse passage between the position illustrated in solid lines in Figure l to the position illustrated in dotted lines at 15-.

Referring particularly to Figures '2, 3, 4, and 5, the details of the casing structure and switching bar-are illustrated. As shown, the inner conductor or probes 11' and 13 are co-axially supported within the threaded 9 connecting

portions

12 and 14 by a single head of di electric material 17. The right hand end of the head is retained in sealed position against the threaded con necting input portion 12 as by an insulating annular washer 13. The central portion of the bead includes a transverse bore 19 registering with the transverse passage 16 of the casing 10 for receiving the switchingbar 15.

The ends of the passage 16 Within the casing 10 tormie nate in annular recesses defining shoulders such as indicated at 2 1 and 21 for co-operation with

end knobs

22 and 23 of the switching bar. These shoulders serve as:

stops. for limiting movement of the switching bar backs. and forth through the transversepassage, 1'5 .asswill-bea evident from Figures 2 and. 3, respectively.

In order to secure the the other, the casing is provided with a lateral bore 24 as best seen in Figures 1 and 4. This bore includes a small ball 25 at its innerend biased towards the central passage 16 by a spring 26 and a set screw 27. The upper end of the switching bar as best seen in Figure 5 in turn is provided with a pair of axially spaced

annular grooves

28 and 29. The arrangement is such that the annular groove 28 will receive the ball when the switch is in the position illustrated in Figures 2 and 4. When the switch is moved to the position illustrated in Figure 3, the ball 25 will then be received in the annular groove 29. This biasing feature, therefore, serves as an indexing means for the switching bar in each of its manually moved positions.

The switching bar 15 as shown in Figlre 5 also includes an axial slot 30 arranged to support and carry a conducting ring 31. The entrance and exit width and length dimensions of the slot 30 are slightly greater than the width and outside diameter of the conducting ring 31 respectively such that the ring may be readily received and move slightly within the slot. The outside diameter of the switching bar at the slot portion, however, is less than the normal diameter of the ring so that diametrically opposite peripheral portions of the ring extend from the entrance and exit portions of the slot.

Referring again to Figures 2 and 3, it will be noted that with the conducting ring 31 in the slot 30, the ring will beretained in the slot by the side walls of the bore 16; The ring is positioned such that its axis is normal to the axis of the transverse passage so that when the switching bar 15 is moved to the position illustrated in Figure 2 opposite diametrical portions of the ring 31 will engage the inner contacting ends 32 and 33, respectively, on the inner conductors 13 and 11. The spacing between these inner contacting ends 32 and 33 is slightly less than the outside diameter of the conducting ring 31 so that upon urging of the conducting ring between the contacting ends, the ring will become slightly distorted within the slot 30 and provides a high contact presure at the diametrically opposite portions of the ring against the contacting areas of the inner ends.

When the switching bar 15 is moved from the position illustrated in Figure 2 to that shown in Figure 3, the ring 31 is moved from between the opposed inner contacting ends thereby electrically opening the switch.

As shown in both Figures 1, 3, and 5, at least a portion of the switching bar 15 is provided with a flat surface as indicated at 34. A corresponding side wall 35 of the transverse passage 16 is also flat to register with the flat portion 34 as shown in Figure 3 so that the switching bar 15 is prevented from rotating about its own axis within the passage 16.

The operation of the switch from the foregoing description will be evident. When the switching bar 15 is moved to the position illustrated in Figure 2, by manually depressing the knob 23, the input conductor 11 is electrically connected through the conducting ring 31 to the output conductor 13. Because of the distortion of the conducting ring 31 which will maintain a high contact pressure at the inner contacting ends 32 and 33 of the conductors, the switching bar 15 will by friction be retained in place. However, the action of the small ball 25 shown in Figure 4 within the annular groove 28 Will further insure retention of the switching bar in the position illustrated in Figure 2.

When it is desired to disconnect the inner conductors, the switching bar 15' is manually pushed upwardly by exerting pressure on the lower knob 21 to the position illustrated in Figure 3 wherein the small ball 25 of Figure 4 will now be received within the annular groove 29. In this position, it will be evident that the conducting ring 31 is totally disengaged from the inner contacting ends of the two conductors 11 and 13 and, therefore, the electrical connection is broken.

switching bar in one position or Moreover, because the switching bar itself is of an insulating material it may be constructed of a light plastic or the like and this feature in combination with the relatively small annular conducting ring provides a relatively light total mass for the moving part of the switch. As a consequence, severe vibrations and high shock loads of the switch will not appreciably affect the desired positioning of the switching bar.

Referring now to Figures 6, 7, and 8, there is illustrated a second embodiment of the invention in which the fOTC',

going principles are provided in a double pole double throw switch.

In Figure 6, there is shown a main casing 37 having

input connectors

38 and 39 and four output lugs or

terminals

40, 41, 42, and 43 extending from an opposite side of the casing 37. As in the case of the embodiment of Figure 1, there is provided a switching bar 44 operable in a transverse bore extending through the casing 37 for effecting the desired switching action.

Referring to Figures 7 and 8, the inner input conductors of the

connectors

38 and 39 are indicated at 45 and 46 and are hereinafter referred to as first and second input conductors. These conductors terminate in inner contacting ends 47 and 48 of relatively increased dimension along the axis of the passage receiving the switching bar 44. These input conductors as well as the various output conductors terminating in the terminal lugs 40, 41, 42, and 43 are insulatively secured within the casing 37 by

annular beads

49 and 50 of di-electric material.

At the top opening portion of the central passage of the casing 37, there is provided a collar 51 having a bore receiving a small ball 52 biased by a spring 53 and a set screw 54. This ball co-operates with annular grooves such as indicated at 55 in Figure 7 and 56in Figure 8 to retain the switching bar 44 in one position or the other.

As shown in both Figures 7 and 8, the switching bar 44 includes two

longitudinal slots

57 and 58 for carrying a conducting ring 59 and an additional conducting ring 60 axially spaced a given distance along the switching bar 44 corresponding substantially to the spacing between the inner contacting ends 47 and 48 of the first and

second input conductors

45 and 46. As in the case of the embodiment of Figures 1 through 5, the switching bar 44 is also provided with a flattened outside surface area 61 along at least a portion of its length for cooperation with a similarly flattened inside wall portion 62 of the transverse bore in the casing 37. By this arrangement, relative rotation of the switching 'bar 44 and casing 37 is prevented.

In the particular embodiment chosen for illustrative purposes in Figures 7 and 8, the

lugs

41 and 43 constitute the end portions of first and second output conductors having inner ends 63 and 64 respectively positioned adjacent the longitudinal passage on opposite sides from the inner ends 47 and 48 of the first and

second input conductors

45 and 46.

The terminal lugs 40 and 42, on the other hand, constitute the ends of additional output conductors having inner ends 65 and 66 spaced respectively from the inner ends 63 and 64 a given distance no greater than the distance through which the switching bar 44 may be moved.

By the foregoing arrangement, and with the switching bar 44 in the position illustrated in Figure 7, it will be noted that the

input conductors

45 and 46 are each respectively connected through the conducting rings 59 and 60 to the output conductor terminal lugs 41 and 43, while the output terminal lugs 40 and 42 are disconnected. When the switching bar 44 is moved upemerge Wardly to the position illustrated in Figure 8, the

same input conductors

45 and 46 are connected through the rings 59 and 60, respectively, to the additional output conductor lugs 40 and 42 and the

terminals

41 and 43 of the first mentioned first and second output conductors are disconnected.

As in the case of the embodiment of Figures 1 through 5, the spacing between the inner ends of the various conductors is slightly less than the outside diameter of the rings 59 and 60 so that slight distortion of the rings is efiected when they are moved between the contacting ends. Thus the advantages heretofore stated of high contact pressure and minimization of interference by vibrations and shock obtain in the double pole double throw configuration as described.

A particular advantage of the embodiment of Figures 6 to 8 resides in the exact switching synchronism between the input conductors and the respective output conductors. This synchronisrn is maintained as a consequence of the use of a rectilinear switching bar structure which moves in the direction of its longitudinal axis. Thus, internal contraction or expansion from switching pressure is negligible and no flexure deformations come into play. Therefore, the spacing between the rings remains fixed at all times.

From the foregoing description, it will be seen that the present invention provides greatly improved electrical switches. Not only are the devices extremely reliable as a consequence of the unique provision of the conducting ring within the switching bar, but the entire assemblies can be made relatively small and of compact form.

Modifications that fall within the scope and spirit of this invention will readily occur to those skilled in the art. The electrical switches are, therefore, not to be thought of as limited to the particular embodiments chosen merely for illustrative purposes.

What is claimed is:

l. A switch comprising: a casing filled with dielectric material and having a transverse passage extending therethrough; a movable switching bar disposed in said passage; two conductors extending into opposite sides of said casing and dielectric material and having their inner ends terminating adjacent to opposite sides of said passage and their outer ends extending to the exterior of said casing, said dielectric material rigidly securing said inner ends in a fixed position so that the spacing between said inner ends is held constant; and a conducting ring of resilient material coupled to said switching bar within said passage and lying in a plane including said inner ends and the axis of movement of said switching bar, said spacing between said inner ends of said two conductors being less than the outside diameter of said ring, whereby movement of said switching bar in one direction urges said ring between said inner ends to electrically connect the same, and resiliently distorts said ring into an oval to apply contact pressure at substantially diametrically opposite portions of said ring in engagement with said inner ends, and movement of said switching bar in an opposite direction removes said ring from between said inner ends.

2. The subject matter of claim 1, in which said switching bar is of insulating material and includes a longitudinal slot of entrance and exit width and length dimensions at least as large as the width and outside diameter of said ring respectively whereby said ring is receivable in said slot.

3. The subject matter of claim 2, in which the ends of said switching bar extend out of said passage to the exterior of said casing to be exposed for manual movement in either direction.

4. The subject matter of claim 3, in which said switching bar includes a pair of axially spaced annular grooves, said casing including indexing means biased against a side of said switching bar, the axial spacing between said grooves corresponding to the movement of said switching bar whereby' said indexing means is receivable in each of said grooves to hold said switching bar in given positions.

5. A switch comprising, in combination: a casing filled with dielectric material and having a transverse passage extend therethrough; a switching bar supported in said passage for back and forth movement along the axis of said passage; a resilient ring of conducting material supported by said switching bar within said passage and positioned with its axis normal to said axis of said passage; a first input conductor extending into said dielectric material and having an inner contacting end positioned adjacent one side of said passage, said dielectric material rigidly securing said end in a fixed position; and a first output conductor extending into said dielectric material and having an inner contacting end positioned adjacent an opposite side of said passage, said dielectric material rigidly securing said last mentioned end in a fixed position so that the spacing between the contacting ends of said input and output conductors is held constant, the outside diameter of said ring being greater than said spacing, whereby movement of said switching bar in one direction moves said ring to distort said ring into an oval shape between the contacting ends of said input and output conductors to distort said ring into an oval shape and thereby electrically connect said input conductor to said output conductor and movement of said switching bar in an opposite direction causes said ring to disengage at least the inner contacting end of said first output conductor.

6. The subject matter of claim 5, including an additional resilient ring of conducting material supported by said switching bar within said passage a given axial distance along said passage from said first mentioned ring; and a second input conductor extending into said dielectric material and having an inner contacting end positioned adjacent said passage at a point axially spaced said given axial distance from the inner end of said first input conductor; and a second output conductor extending into said dielectric material and having an inner contacting end positioned adjacent to an opposite side of said passage from said inner end of said second input conductor, said dielectric material rigidly securing said contacting end of said second input conductor and said contacting end of said second output conductor in fixed po sitions so that the spacing therebetween is held constant, the outside diameter of said additional ring being greater than said last mentioned spacing, whereby movement of said switching bar in said one direction simultaneously moves said additional ring between said contacting ends of said second input and output conductors to distort said additional ring and electrically connect said ends of said second input and output conductors and movement of said switching bar in said opposite direction causes said additional ring to disengage at least the inner contacting end of said second output conductor.

7. The subject matter of claim 6-, in which the inner ends of said first and second input conductors have elongated surfaces in the direction of movement of said switching bar to maintain contact with said first mentioned and additional rings respectively when the same are moved out of engagement with the inner ends of said first and second output conductors respectively; and two additional output conductors extending into said dielectric material and having inner ends disposed in a position to engage said first mentioned and additional rings respectively when said switching bar is moved to said position out of engagement with the inner ends of said first and second output conductors whereby a double pole double throw switch is provided.

References Cited in the file of this patent UNITED STATES PATENTS 1,889,515 Hammerly Nov. 2,9, 193;