US 3733577 A
An improved two-part connector of which one part has one or more bayonet pins while the other part is fitted with a coupling ring adapted to telescope over the one part. The coupling ring has an internal annular groove which receives an annular spring strip in the form of a band having one or more pairs of spring jaws facing forwardly of the coupling ring, the spring jaws being adapted to snap over the bayonet pin or pins of the one part when the two parts are mated.
Description (OCR text may contain errors)
mite totes tet Hammond May 15, 1973 ELECTRICAL TWO-PART CONNECTORS Peter George Henry Hammond, Whitstable, England The Bunker-Ramo Oak Brook, 111.
Filed: Feb. 16, 1971 Appl. No.: 115,475
Foreign Application Priority Data Feb. 16, 1970 Great Britain ..7,332/70 Nov. 20, 1970 Great Britain ....55,380/70 US. Cl ..339/91 R, 24/201, 285/305,
285/DIG. 22, 287/D1G. 7 Int. Cl. ..H01r 13/54 Field of Search ..339/69, 70, 73, 74,
339/76-79, 90, 91; 285/D1G. 22, 305, 317, 319, 404; 287/D1G. 7, 119; 24/201, 230 R  References Cited UNITED STATES PATENTS 3,207,536 9/1965 Lawrence ..339/91 R 3,513,436 5/1970 Nodfelt ....339/90 R 2,194,769 3/1940 Reed ....339/91 R 3,368,182 2/1968 Culver ..339/91 R FOREIGN PATENTS OR APPLICATlONS 1,045,762 7/1953 France ..339/91 R 481,485 12/1969 Switzerland ..339/103 R Primary Examiner.loseph H. McGlynn Attorney- Frederick M. Arbuckle  ABSTRACT An improved two-part connector of which one part has one or more bayonet pins while the other part is fitted with a coupling ring adapted to telescope over the one part. The coupling ring has an internal annular groove which receives an annular spring strip in the form of a band having one or more pairs of spring jaws facing forwardly of the coupling ring, the spring jaws being adapted to snap over the bayonet pin or pins of the one part when the two parts are mated.
5 Claims, 3 Drawing Figures Patented May 15, 1973 FEGI Jilnlh \NVENTOR PETER 6H. HAMMOND ELECTRICAL TWO-PART CONNECTORS BACKGROUND OF THE INVENTION 1. Field of the Invention The field of art to which the present invention pertains is that of electrical two-part connectors of the type in which the two mating parts of the connector are maintained in a mating locked position by a snap or snatching action when the mating parts are connected.
2. Description of the Prior Art One common form of known electrical two-part connector has one or more bayonet pins on a male connector plug body and a coupling ring rotatable on a mating female receptacle body, the coupling ring having bayonet slots therein corresponding to the bayonet pins on the plug body. The two parts are drawn together when the coupling ring is rotated to cause the pin to ride up the slots of the coupling ring. Such a connector requires the coupling ring to be rotated in the opposite direction to effect disconnection of the parts. Requirements exist, however, for connectors which will disconnect simply in response to a pull, such connectors being designated in the art as snatch connectors.
Many designs for snatch connectors exist, of varying degrees of complexity, but all have distinguishable disadvantages, in that generally they are quite complex and thus difficult to manufacture, and generally are not suitable for mating with corresponding mating connectors already implemented in existing equipment systerns.
SUMMARY OF THE INVENTION In view of the need in the art of a simple snatch type connector, but yet one which can easily be adapted to present manufacturing equipment and be relatively compatible with existing mating connectors, it is an object of the present invention to provide an electrical two-part connector which is simple in construction but which is nevertheless structured so as to require only minor manufacturing modifications of conventional bayonet type connectors to be compatible therewith. This enables the manufacturer of a variety of bayonet connectors to supply the same selection or range 'of connector types to his customers in the alternative snatch connector version, with only small additional tooling costs and stock-carrying requirements.
According to the present invention, there is provided an electrical two-part connector of which one part has one or more bayonet pins, while the other part is fitted with a coupling ring adapted to telescope over the one part, the coupling ring having one or more pairs of spring jaws fitted therein or integral therewith and facing forwardly of the open end of the coupling ring so as to snap over the bayonet pin or pins when the two parts are mated.
It will be appreciated that the male plug body portion of the connector, carrying the bayonet pins is of the type presently being used with conventional bayonet type connectors and accordingly requires no modification whatsoever. The female receptacle body may also be manufactured without change or modification provided that the conventional coupling ring rotatable thereon be replaced with a coupling ring in accordance with the present invention, in order to change a conventional bayonet connector into a snatch-type connector.
The pairs of spring jaws in a preferred embodiment of the invention are arranged on a length of resilient band formed of either a synthetic material or metal which is bent into an annular form, inserted into the forward end of the coupling ring, and maintained therein by the resilient biasing force it exerts on the inner surface of the coupling ring.
It will be particularly noted that conventional bayonet connectors are normally constructed to create a certain mating pressure between the connector parts when the coupling ring is rotated on the bayonet pins to the coupled position. The snatch connector of the 'present invention, on the other hand, is arranged so as to establish a mating pressure by arranging the spring jaws of the coupling ring to grip the bayonet pin or pins of the plug body, thereby tending to draw the plug body into the open end of the coupling ring. Thus, while major portions of the connector (both male and female) are constructed of presently available parts, the unique action of the coupling ring and spring jaws of the subject invention result in a significantly different and improved means of drawing the two parts of the connector together.
BRIEF DESCRIPTION OF THE DRAWINGS Theinvention will be described in more detail, by way of example, with reference to the figures of the ac companying drawings, in which:
FIG. 1 is a view of a coupling ring in axial crosssection and the plug body and receptacle body in vertical elevation;
FIG. 2 is a view of the structure comprising the pairs of spring jaws prior to flexing of the spring to fit internally of the coupling ring; and
FIG. 3 is a fragmentary view of a single spring jaw pair showing one pin in the snatched position within the aw.
DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIGS. 1 and 2, the two principal parts of the two-part connector are shown as male body plug 10 and female receptacle body 16. The plug body 10 houses socket contacts, one of which is indicated schematically at 12. The body 10 has three bayonet pins 14 projecting radially therefrom at intervals.
The receptacle body 16 comprises pin contacts, one being shown schematically at 18, which mate and electrically contact corresponding ones of the socket contacts 12 of the plug body 10 when the two parts are joined.
The pin contacts 18 are shrouded within the forward end 20 of a coupling ring 22 which is rotatably mounted on the receptacle body 16, e.g., by means of a circlip (not shown) engaging in an annular groove 24 inside the ring 22.
As viewed externally of the connector, the coupling ring has the appearance not unlike an ordinary bayonet coupling ring, with the exception that the conventional bayonet slots are not formed on the forward end 20 of the ring 22, as in prior art connectors. Instead, the forward end 20 is relieved internally so as to form an annular groove 26 which opens forwardly at 120 intervals, forming wide slots 28 on the inner front surface of the coupling ring 22. The slots 28 are of such dimension as to leave projections or lands 30 between the slots 28 of even greater width than the slots 28.
The lands 30 serve to retain a spring strip in the forward end of the ring 22, the strip being formed of a length of tough resilient synthetic material, or-of a metal if preferred, which is bent into a circle and sprung into the forward end 20. The spring strip comprises a band 32 which enters the groove 26 and is prevented from being pulled out axially by the spring strip abutting the walls of the groove 26 and is prevented from rotation in the ring 22 by the spring strip abutting the walls of the slots 28. In the preferred embodiment, three pairs of jaws 34 project forwardly from the band 32 through the slots 28.
Each pair of jaws 34 has a flared mouth 36 into which one of the bayonet pins 14 can be pushed to spread the jaws apart. The smaller dimensioned end of the mouth 36 opens into a circular aperture 38. When the pins 14 enter the apertures 38, the jaws snap together again and hold the two parts of the connector together until a sufficient pull separates the two parts. The required pull or separating force can be established by selectively designing the jaws 34 to suit the particular application contemplated.
The ring 22 is drilled with three radially directed holes 40 through which the pins 14 can be seen when the pins 14 are fully home in the apertures 38.
As indicated earlier, the snatch connector of the present invention is arranged to establish a mating pressure between the two connector parts by designing the spring jaws 34 of the band 32 so as to grip the bayonet pin or pins, thereby tending to draw the same into the coupling ring 22. When the pins 14 are snapped into the circular apertures 38, they are thus not loose therein. Rather, the pins are gripped by the shoulders 42 formed where the apertures 38 meet with the flared mouth portion 36 of the jaws 34. These shoulders direct forces against the pin 14 that are directed axially inwardly with respect to the forward end 20 of the coupling ring 22, and therefore act against the cylindrically-shaped pin 14 to cam the pin into the coupling ring. Utilizing a suitable design for the dimensions between the ends of the connector bodies 10 and 16, together with the respective dimensions of the pin 14 and the apertures 38, a mating pressure is established between the plug body 10 and the receptacle body 16 when the pin is under camming pressure. The camming action between the shoulders 42 and pin 14 is illustrated in FIG. 3, which shows a fragmentary portion of the band 32, one of the pair of jaws 34 having captured a pin 14 which had been forced between the jaws 34 through the flared mouth 36 and into the FIG. 3 position within aperture 38.
In the FIG. 3 position, the shoulders 42 exert force in the direction of arrows 43 as the jaws 34 spring together. As the shoulders 42 cam against the pin 14, a component of force in the direction of arrows 44 is also generated. In this manner, while the pin 14 is, as shown in FIG. 3, somewhat smaller in diameter than aperture 38, the pin 14 is not loosely fitted within the aperture in the coupled position of the connector.
The connector parts are designed to separate in response to a direct pull on the cables which are con- I may therefore attempt to rotate the coupling ring 22 relative to the plug body 10. This inadvertent act, however, will not cause any damage to the connector because the jaws 34 of the spring strip will merely be pushed against the lands 30 and cannot be forced beyond such a position.
The use of a spring strip sprung into a coupling ring enables the production of a coupling ring having a conventional external appearance, e.g., a narrowed metal ring, while the particular structure internally thereof provides the convenience and speed of connecting and disconnecting which is associated with snatch-type connectors. Thus, the advantages of a snatch-type connector is realizable concomitant with being simple and inexpensively produced.
It is contemplated that the jaws 34 could be provided using various manufacturing techniques. As an example, the ring 22 could be molded from a tough, resilient synthetic material, the jaws being molded integrally therewith. Alternatively, the coupling ring could be produced from metallic material and the band 32 could be produced from synthetic material and/or from a sheet metal material by stamping operations.
Since the receptacle body 16 is intended to be adapted with the unique coupling ring in accordance with the present invention, the body members 10 and 16 are considered to be parts which are presently available on the market. Thus, the present invention is related specifically to the coupling ring 22 and the band 32 mounted therein. The coupling ring 22 and band 32 can be sold separately, e.g., as an adaptor which the user can fit onto existing connectors as a replacement for their ordinary bayonet coupling rings, thereby effecting conversion of the connector to a snatch-type connector.
With specific reference to FIG. 2, it will be seen that the coupling ring and spring jaws are manufacturable with the band 32 having generally straight portion 33 with the three pairs of jaws 34 projecting laterally therefrom. In use, this strip is bent into a circle and snapped into the coupling ring. As shown in FIGS. 2 and 3, the jaws preferably have a mouth 36 which is flared and tapers inwardly toward the straight part 33 of the band 32 and then opens into an enlarged aperture 38 for receiving the bayonet pin 14.
It will be apparent that the spring strip insert band 32 can easily be pried out of the coupling ring 22 and a new band snapped into place, if replacement is needed for any reason. It will also be noted that the form of the band 32, with relatively short jaws 34, will allow the band to be accommodated in the coupling ring 22 without increasing either its axial or its radial dimensions beyond that of conventional bayonet type connectors. Externally, the coupling ring can be identical with the ordinary bayonet coupling ring which it replaces.
When the connection is made or broken, the jaws 34 flex open by the action of the jaws 34 bowing and twisting to accommodate the pin 14. Pin 14 is designed to be of larger diameter than the smallest dimension of the flared mouth 36 but of smaller diameter than the aperture 38. The twisting character of the jaws 34 is particularly effected at the roots of the jaws where they merge into the straight portion 33 of the band 32. However, it will be appreciated that the band itself may bow or twist laterally in the narrowed region thereof adjacent the aperture 38. In order to permit twisting of the straight portion 33 of the band 32 itself, the axial width of the band 32 may be designed to be somewhat less than the axial width of the annular groove 26 which receives the band 32.
While the invention has been particularly shown and described with reference to a preferred embodiment thereof, it will be understood by those skilled in the art that the foregoing is an example only, and that other changes in form and detail may be made therein without departing from the spirit and scope of the invention.
What we claim is:
l. A first connector part for receiving a mating second connector part having at least one radially directed projection thereon, said first part comprising a cylindrical body and a coupling ring coaxial with and rotatable on said body, said coupling ring enclosing at least one pair of axially extending jaws adapted to receive and retain said projection when said first and second connector parts are brought together, said coupling ring having an annular forward portion which provides a shroud for said jaws, and at least one aperture in said forward portion through which said projection is observable when said connector parts are brought together.
2. A first connector part for receiving a mating second connector part having at least one radially directed projection thereon, said first part comprising a cylindrical body, a coupling ring carried thereon and coaxial therewith, having an annular internal groove, intersected by at least one axial internal groove extending from said annular groove to the outer end of said coupling ring, and a spring received in said groove, said spring having at least one axially-opening jaw thereon adapted to receive and retain said radially directed projection when said connector parts are mated, said jaw being received in said axial groove.
3. The invention as defined in claim 2, wherein the spring is of normal curvature less than that of said groove, so that when fitted therein it exerts outward force.
4. The invention as defined in claim 2, wherein said jaw consists of a pair of opposed members defining a flared mouth with its large end toward the outer end of said coupling ring, and its smaller end opening into a first aperture of interrupted circular outline larger than said projection.
5. The invention as defined in claim 4, wherein said coupling ring includes a second aperture radially aligned with said first aperture, through which said projection is observable when said connector parts are brought together.