US3599671A - Fluidic switch - Google Patents

Abstract

A four-way switch of particular utility in fluidic computation and control apparatus is disclosed herein. The switch comprises a pivotable switching and control member having a flat surface resiliently biased toward a plane surface of the housing. The plane surface of the housing is perforated in three locations with the perforations being communicated to three mutually independent fluid outlets. The pivotal member includes, on the surface opposed to the flat surface, a detent receiving means for holding the member in either of two pivotal positions and on the flat surface, a channel adapted to intercommunicate the center perforation with either of the other perforations. The pivotal member is further perforated by two passages arranged to communicate the third of the housing member perforations through the valve to the ambient to vent the unused passage system.

Description

United States Patent Inventor Stanley Leszczynski Schenevus, N.Y. 2i Appl. N0. 826,519 22 Filed May 21, 1969 I45] Patented Aug. 17,1971 |73| Assignee The Bendix Corporation [54] FLUIDICSWITCH 3 Clalms,4 Drawing Figs. 52 U.S.Cl tar 625.21

[51] lnt.Cl ..Fl6k 11/02 [50] FieldofSearch ..137/625.21, 596;251/297, 180,295

[5 6] References Cited UNITED STATES PATENTS 7 856,652 6/1907 Murphy l37/625.2l 1,938,505 12/1933 Trice et aL... 251/297X 1,969,462 8/1934 Hodgkins l37/625.21 X 2,351,732 6/1944 Almond et al.. 137/624.21 2,377,473 6/1945 Wolcott 251/297X 3,082,791 3/1963 Miller 251/180X FOREIGN PATENTS 1,027,633 4/1966 Great Britain Primary ExaminerM. Cary Nelson Assistant Examiner-R. B. Rothman Attorneys- Robert A. Benziger and Flame, Arens, l-lartz, l-lix and Smith ABSTRACT: A four-way switch of particular utility in fluidic computation and control apparatus is disclosed herein. The switch comprises a pivotable switching and control member having a flat surface resiliently biased toward a plane surface of the housing. The plane surface of the housing is perforated perforated by two passages arranged to communicate the third of the housing member perforations through the valve to the ambient to vent the unused passage system.

PATENTEDAUGI'IIQYI v 3599.671

FIGURE 4- h FIGURE 3 FIGURE I STANLEY LESZCZYNSK/ INVENTOR.

FLUIDIC SWITCH BACKGROUND OF THE INVENTION 1. Field of the Invention v ,The present invention relates to switches adapted to switch fluid flow in systems, particularly in systems utilizing fluidic logic components.

2. Description of the Prior Art The prior art shows a wide variety of means to switch fluid flows between a plurality of passages. However, these means are not wholly consistent with the primary objectives and advantages of fluid logic control systems (fluidics) since the prior art devices do not combine all of the necessary attributes of a fluidic switch.

In switching fluid flows in systems employing fluidic logic components, several important considerations must be-borne in mind. There must be a minimum leakage consistent with maintainingoperating pressures throughout the system, but small amounts of leakage at the switch are acceptable since fluidic logic systems utilize venting (controlled leakage) to isolate elements. Furthermore, the expense of such a device must be consistent with fluidic systems which are, in general, low expense. systems. It is, therefore, an object of the present invention to provide a low cost switch construction adapted for fluid handling systems.

As well as being low in cost, a fluid switch must also have a long useful service life. It is, therefore, an object of the present invention to provide a fluid switch having a long service. It is a further object of the present invention to provide such a switch which is substantially rigid in constructionhaving a minimum of moving parts. It is a further object of the present inventionv to provide such a switch in which wear due to long term usage does not effect part alignment.

Switches used in. fluid handling systems, such as fluidic logic control circuitry, are frequently required to communicate a source of pressurized fluid to at least one of a plurality of circuit fluid sources or utilization means. It is, therefore, an object of the present invention to provide a fluid handling switch adapted for fluid systems of the kind utilizing fluidic logic components and adapted to intercommunicate a fluid source with at least one of a plurality of fluid utilizing systems. In order topermit such fluid utilizing systems to become emptied when not connected to the source of fluid pressure, it is a further object of the present invention to provide a fluid switch which is low in cost and is adapted to intercommunicate a source of fluid with at least one of a plurality fluid utilizingsystems which also includes means for automatically venting the unused fluid utilizing systems.

Keeping in mind the above objective to provide a switch which is simple in construction and low in cost, while providing means for venting fluid utilization circuits not currently in use, it is a still further object of the present invention to provide a fluid switch having a substantially arcuate shaped rocker member having a flat surface perpendicular to the axis of rotation which cooperates with a perforated flat surface on the switch body to perform the switching function with the flat surfaces further cooperating to provide sealing for the intercommunication sufficient to prevent leakage of fluid in excess of the maximum permissible in a fluid logic system.

SUMMARY OF THE INVENTION The present invention comprises a rocker switch portion pivotally mounted in a housing with the pivotal member having a flat surface resiliently biased toward a cooperating surfaceof the housing such that switching is achieved by a channel in the rocker member flat surface and the cooperating surfaces, assisted by the resiliently biasing detent mechanism, provide a fluid seal. The rocker switch portion is further perforated to provide the necessary venting of the unused fluid utilizing systems.

BRIEF DESCRIPTION OF THE DRAWING DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to FIGS. 1 and 2, a switch 10, according to the present invention, is shown with aportion of the switch body 12 broken away in FIG. 1 to illustrate the'resiliently biasing detent means 14. The detent means 14 comprise a resilient member 16 having a projecting tab or finger 18 from which protrudes convexity 20 which is operative to engage concavi- -ties 22 and 24 on the side of rocker switch member 26. The

rocker member 26 is pivotably mounted on pin 28 which, as is best shown in FIG. 2, is mounted in the switch body 12. Since the rocker member 26 is shown as being comprised of the major segment of a right circular cylinder, it should be readily apparent that the member 26 could be restrained for pivotal movement about an axis by replacing pins 28 with restraining guide means located at strategic points around the periphery of the member 26.

The resiliently biasing detent mechanism 14 is connected to the switch body 12 by conventional means, shown here as threaded bolts 30 and 32. Fluid coupling members 34, 36 and 38 are shown extending from the lower portion of body 12 and which, as best shown in FIGS. 2' and 3, communicate with fluid passages extending into the body 12 to ultimately communicate with the flat switching surface 27 of rocker member 26. Cover plate 13 is connected to body 12 to provide a complete switch module.

Referring now to FIG. 2 wherein a sectional view of the switch of FIG. I is shown, the relationship between the switch body 12, detent means 14 and rocker member 26 is. more clearly illustrated. In the switch position illustrated, convexity 20 is shown as received by concavity 24 so as to maintain the switch in a stable position. The resilient finger 18 is operative to maintain the switch position and is also further operative to bias the rocker member 26 towards the switch body- 12.

Referring now to FIGS. 3 and 4, particular emphasis is placed on the relation between the fluid passages in the switch body 12 and the channel and passages in the pivotal member 26. Each fluid coupling 34, 36 and 38 communicates directly with a fluid conduit or passage 40, 42, 44 which, with reference to FIG. 2, rises upwardly into the body of the switch and then turns toward the pivotal member26 where each terminates in an orifice. Each orifice is positioned an equal distance from the pivoting axis, located in this preferred embodiment at the pin 28.

Referring now specifically to FIG. 4, the pivotal member 26 is shown in an elevational view. The pivotal member 26 includes two passages 52 and 54 which pass through the pivotal member 26 and lie on either side of a channel 56 positioned at the center of the arc circumscribed by the arcuate section of the switch. The passages 52 and 54 and the channel 56 are substantially equidistant from the pivotal axis and are arranged to coincide with the orifices 46, 48 and 50 of the passages 40, 42 and 44 so that the channel will intercommunicate the center orifice 48 with either of the outer orifices while one of the passages 52 and 54 will communicate the other orifice to the ambient pressure existing on the other side of the switch.

In operation, the center fluid coupling 36 is connected to a source of pressurized fluid so that the fluid is communicated to the passage 42 and thence to the channel 56-. In one position the channel communicates the pressurized fluid to one of the outer passages 40 and 44, while the other of the passages is communicated, via either of passages 52 and 54, through pivotal member 26 to the opposite side thereof to serve as a means for venting the nonused fluid circuit. Since surface 27 is flat and mates with a similarly flatsurface on switch body 12 and the pivotal member is permanently biased toward the switch body 12 by resilient finger 18, there exists a very low leakage virtual seal for fluid through the channel 56. The detent and biasing means 14 prevents inadvertent switching, but due to the small amount of penetration of the concavities 22 and 24 by the convexity 20, intentional switching is not inhibited. By suitable choice of material for the pivotal member, the large contact surface will not inhibit the switching action. Furthermore, since all forces exerted on the pivotal member 26 are substantially parallel with the pivotal axis, any wear which would occur will not alter the relationship between the various passages in the body 12 and in the pivotal member 26. This has the advantage of maintaining fluid flow and adequate sealing over the life of the switch with the minimum moving parts, the pivotal member 26 and the resilient finger 18.

I claim:

l. A fluid switch comprising:

a switch body having a substantially flat surface and a plurality of passages passing through said body and having orifices in said flat surface;

a switch member retained in said body and having a substantially flat surface arranged in sliding contact with said switch body flat surface and a side opposite to said flat surface;

means for pivotally retaining said switch member in said switch body providing said switch member with a pivotal axis perpendicular to said flat surfaces;

said orifices arranged to be equidistant from said pivotal axis;

biasing means operative to bias saidflat surfaces into contactive sliding engagement; said switch member including a plurality of passages passing therethrough, each of said passages having an orifice in the switch member flat surface equidistant from said pivotal axis, and a channel formed in said flat surface, said channel being adapted to intercommunicate two of said body passage orifices; said flat surface further operative to provide a fluid seal surrounding the orifices of said plurality of passages and said channel; 1

said switch member passage orifices and said switch body passage orifices being substantially the same distance from said pivotal axis; means formed in said opposite side of the switch member operative to receive pressure from said biasing means whereby switch position may be maintained in any one of a plurality of positions; and

said switch member is comprised of a major arcuate segment of a right circular cylinder and said channel is positioned at the center of the arc circumscribed by said arcuate segment.

2. The switch as claimed in claim 1 wherein said plurality of switch body passages is at least three in number.

3. The switch as claimed in claim 2 wherein said switch member passages are adapted to communicate one of said at least three switch body passages through said switch member when said channel is intercommunicating two of the remaining at least three switch body passages.

Claims (3)

1. A fluid switch comprising: a switch body having a substantially flat surface and a plurality of passages passing through said body and having orifices in said flat surface; a switch member retained in said body and having a substantially flat surface arranged in sliding contact with said switch body flat surface and a side opposite to said flat surface; means for pivotally retaining said switch member in said switch body providing said switch member with a pivotal axis perpendicular to said flat surfaces; said orifices arranged to be equidistant from said pivotal axis; biasing means operative to bias said flat surfaces into contactive sliding engagement; said switch member including a plurality of passages passing therethrough, each of said passages having an orifice in the switch member flat surface equidistant from said pivotal axis, and a channel formed in said flat surface, said channel being adapted to intercommunicate two of said body passage orifices; said flat surface further operative to provide a fluid seal surrounding the orifices of said plurality of passages and said channel; said switch member passage orifices and said switch body passage orifices being substantially the same distance from said pivotal axis; means formed in said opposite side of the switch member operative to receive pressure from said biasing means whereby switch position may be maintained in any one of a plurality of positions; and said switch member is comprised of a major arcuate segment of a right circular cylinder and said channel is positioned at the center of the arc circumscribed by said arcuate segment.

2. The switch as claimed in claim 1 wherein said plurality of switch body passages is at least three in number.

3. The switch as claimed in claim 2 wherein said switch member passages are adapted to communicate one of said at least three switch body passages through said switch member when said channel is intercommunicating two of the remaining at least three switch body passages.

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