US 3029406 A
Description (OCR text may contain errors)
April 10, 1962 c. M. HUTH 3,029,406
CONNECTOR Filed June 25, 1958 IN V EN TOR. C'A/F'L M. HUT/'7 Uite The present invention relates generally to electrical connectors and more particularly to an improved bayonet type connector.
Electrical apparatus, such as tools, appliances, business machines, etc., are often connected to a source or power, or to each other, through electrical cables which can be disconnected and removed when not in use. Also, in certain applications pieces of electrical apparatus are located at a distance from each other or from the power source which may require the electrical cable to be in sections. A bayonet type connector is commonly used as a connection between cables, or between a cable and an electrical appliance.
Normally, a bayonet type connector comprises a plug having a generally cylindrical body and a locking pin which extends radially from the surface thereof, and a complementary tubular receptacle which has a hooked shaped slot in its wall that is adapted to receive the locking pin of the plug. A bayonet type connector has an advantage of being easily connected or disconnected when desired and, yet, is locked in such a manner that it will not become inadvertently disconnected during use.
Other advantages of using a bayonet connector as a connection between an electrical apparatus and a cable, or between cables, are maximum safety and long life for the cable, and maximum convenience for the user.
Various forms of locking or latching pins have been used to retain a bayonet connector in its associated tubular receptacle. In a previously available bayonet type connector plug having a body portion composed of rela tively soft dielectric material, the looking or latching pin included a head embedded in the dielectric material, Because of the space limitations and the severe usage to which a bayonet type connector may be subjected, a headed pin of the maximum allowable dimensions has a tendency to pull out of the relatively soft material or deform the dielectric material about the pin and, thus, terminate the useful life of the bayonet connector and its attached cable.
The principal object of the present invention is to provide a bayonet type connector having a locking or latching pin so designed, constructed, and anchored in the body that it will not be displaced even when subject to rough handling and will not deform any part of the body.
A further object of the present invention is the provision of a bayonet type connector, which has a locking pin arranged in the dielectric material of the connector, that is rugged, durable, and economical to manufacture.
Further objects and advantages of the present invention will become apparent from the following description and accompanying drawing.
In the drawing:
FIGURE 1 is a perspective view of one embodiment of a bayonet type connector, made in accordance with the present invention, the connector plug and the receptacle being shown in a disengaged condition; y
FIGURE 2 is another perspective view of the recep tacle shown in FIGURE 1;
FIGURE 3 is a side view of the bayonet type connector plug shown in Fl-GURE l with a portion cut away to show its inner construction;
FIGURE 4 is a sectional view taken along line P4 of FIGURE 3; and v ice FIGURE 5 is a side view of another embodiment of the bayonet type connector plug formed in accordance with this invention, with a portion cut away to show its inner construction.
A bayonet type connector plug, formed in accordance with this invention, is designated in the drawing by the reference numeral 9. This connector plug includes a body 10 of resilient dielectric material having a generally cylindrical end portion 12, at least one contact member 14 fixedly carried by the body 10 and accessible to another contact member 16 carried by a complementary receptacle 18. A locking or latch pin 20 of a hard material is embedded in the end portion 12. This locking pin 29 has a part 22 which extends radially outwardly from the dielectric material far enough to co-operate with a bayonet slot 24 in the receptacle 18 and has an integral portion or limb 26 which extends along and within the body 10 and is spaced from the exterior of the body 10.
The bayonet type connector plug E is adapted to be interengaged with a complementary bayonet receptacle such as that illustrated in FIGURES 1 and 2, which is designed to be arranged so as to extend inwardly from an aperture in a Wall of an electrical appliance. The bayonet receptacle 18 includes a tubular body or sleeve 23 which is formed of metal or similar material.
The tubular body 28 has a longitudinally movable and rotatable member 30 disposed therein. This rotatable member 39, which is composed of a dielectric material, is circular in transverse cross section and has a pair of bosses 32 extending outwardly from its side wall. The bosses 32 are disposed so as to operate in diametrically opposed slots 34 in the wall of the tubular body 28. These slots 34 in combination with the bosses 32 serve as a stopping means for the outward movement of the member 30, and are arranged so as to allow the member 30 to be rotatable and movable longitudinally. Accordingly, the slots 34 each include a section 36 extending longitudinally from the rear edge of the body portion 28, and a second section 38, larger in width, which extends at an angle to the first section 36 and is terminated intermediate the ends of the tubular body 28.
At least one contact member 16 is attached to the rotatable member 30. In the illustrated embodiment the receptacle 18 has three male contact members 16 and the connector plug 9 has an equal number of female contact members 14. It should be understood, however, that the number, form, and type of contact members may be varied, e.g. the female contact members may be arranged within the receptacle 18 and the male contact members arranged in the connector plug 9, or button contacts may be used.
vIn the illustrated embodiment, the male contact members 16, which are in the form of elongated cylinders with rounded outer ends, extend outwardly from, and are suitably mounted to the rotatable member 30. The rearward end portion of each of the male contact members 16 extends through the rotatable member 30, and is suitably connected to an electrical conductor 40 by soldering or the like.
An urging means 42, biases the rotatable member 30 outwardly to a position where each of the bosses 32 abuts against the forward edge of each of the slots 34. This urging means 42 may be in the form of a coil spring which is arranged within the tubular body 28 between the rearward surface of the rotatable member 30 and suitable tabs 44 extending inwardly from the rearward edge of the tubular body 28.
The receptacle 18 may be supported within an electrical appliance by means of a pair of diametrically opposed, outwardly extending tabs 46 located near the forward edge of the tubular body 28. In the illustrated embodiment, these tabs 46 are struck out of the wall of the tubular body 28. A mounting hole 48 is arranged centrally in each of the tabs 46 so that the receptacle 13 can be adequately mounted to the electrical appliance by means of screws or the like.
The slot 24 is arranged in the wall of the tubular body 28 in such a way that it extends rearwardly from the forward edge of the tubular body 28, and is terminated in a hook shaped, rearward end portion 50 adjacent the outermost position of the rotatable member 30. As is described subsequently, the outwardly extending part 22 of the locking pin 20 on the connector plug 9 is inserted into this slot 24 and is locked in position in the hookshaped rearward end 56 thereof.
The body of the connector plug 9 is preferably composed of relatively soft, resilient dielectric material, which may be readily and economically formed or molded, such as thermo-plastic resin. The body 10 may take a variety of shapes and forms, taking into consideration the various requirements of manufacturing techniques employed, the number, sizes and type of contact members used, and the decorative exterior design desired. In the illustrated embodiment, the body 10 is composed of the cylindrical forward end portion 12 and a tapered rearward end portion 52. The forward end portion 12 has a diameter which is slightly smaller than the tubular body 28 of the bayonet receptacle 18 into which it is received.
The rearward end portion 52 is elongated so as to act as a strain relief for its associated cable or cord 54. This rearward end portion 52 is tapered rearwardly, and a shoulder 56 is formed at the rear end thereof. The rearward end portion 52 is formed with a plurality of longitudinally extending raised ribs 58 arranged thereon which serve as gripping means so that the connector plug 9 can be easily rotated in the receptacle 18, as is described subsequently.
Female contact members 14, equal in number to the male contact members 16in the receptacle 18, are molded into the body 10 of the connector plug 9 so as to extend longitudinally therein. Each of the female contact members 14 is accessible to the complementary male contact member 16 through an opening in the face of the end portion 12. The other end of each of the female contact members 14 is connected to an electrical conductor 60 by soldering or the like.
These female contact members 14 may be of any de sired form. In the illustrated embodiment, each of the female contact members 14 includes and elongated tubular body portion 61 which is arranged adjacent the face of the end portion 12 and has an arcuate cross section, and a crimping portion 63 which is in end to end relationship with the tubular body portion 61, and has a pair of ears (not shown) that are used to crimp the electrical conductor 60 to the contact member 14.
Ordinarily, the electrical conductors 60, that are connected to the contact members 14, have an outer insulating sleeve. In the illustrated embodiment, these conductors 60 are longitudinally arranged in adjoining relationship and covered by an outer sheath to form the cable 54. For ease of manufacture, and for the strength of the resultant mechanical bond, the body 10 of the connector plug 9 may be molded directly onto the cable 54. The other end of each of the electrical conductors 60 within the cable 54 may be connected to a suitable contact member of a plug (not shown). This plug may also be molded directly onto the cable 54.
The locking pin is preferably generally U-shaped, and is composed of a hard material, such as metal. The locking pin 20, which may be constructed by bending a section of wire to the desired shape, is preferably embedded in the material of the body 10 during the mold ing process. It is arranged so that its legs 62 and 64 extend radially outwardly and the portion or limb 26 which connects the legs 62 and 64 extends generally longitudinally within the body 16, and is spaced from the exterior of the body 10 and from the contacts 14 higher current requirement.
within the body 16. One of the legs 62 of the locking pin 20 is of sufiicient length such that the end part 22 thereof extends outwardly from the dielectric material. It is arranged at such a distance from the face of the connector plug 9 that, when the connector plug 9 and the receptacle 18 are being inter-engaged, the rotatable member 30 must be pushed rearwardly so that the outwardly extending part 22 of the loclzing pi 26' can clear the lip of the hook-shaped rearward end 50 of the slot 24 so as to allow the connector plug 9 to be rotated into its interengaged position. In this way, when the connector plug 9 is interengaged with the receptacle 18, the outwardly extending part 22 of the locking pin 20 is maintained within the hooloshaped rearward end portion 50 by spring tension.
The other leg 64, which is disposed further away from the face of the connector plug 9 than the first mentioned leg 62, is made of sufficient length such that the end thereof is approximately flush with the surface of the forward end portion 12.
The locking pin may also be made generally L-s'1apcd as illustrated in FIGURE 5. In this embodiment since the second mentioned leg 64 is eliminated, the longitudinally extending limb 26a of the locking pin 20:: is made longer so as to resist any tendency of the locking pin 20a to be pulled out of the dielectric material.
The width of the end part of locking pin 26, transverse of the forward end portion 12, is such that it is slidable into the slot 24 in the receptacle 18. Because of the danger involved in using a cord having an insufficient current rating, it is desirable to positively prevent a connector plug which is connected to a cord having an insutficient current rating from being inserted into a receptacle which is connected to an appliance having a This may be accomplished by making the outwardly extending part of a locking pin on a higher rated cord, narrower than that of a lower rated cord. Correspondingly, the slots in the respective receptacles are varied in width.
The width of an outwardly extending portion of a locking pin can be varied either by embedding a locking pin formed of a wire of the proper diameter or, preferably, because the difiiculty in bending a larger diameter wire, by embedding a locking pin formed of a generally rectangular (mill edge) wire, in which the longer side of the rectangle, which is disposed parallel to the face of the end portion, is the proper size.
In order to interengage the connector plug 9 with the receptacle 18, the outwardly extending part 22 of the locking pin 20 is arranged opposite the slot 24 in the receptacle 18, and then the connector plug 9 is inserted therein. As the connector plug 9 is received by the receptacle 18, the complementary contact members 14 and 16 are interengaged. When the face of the connector plug 9 is approximately abuttcd against the rotatable member 30 of the receptacle 18, a longitudinal force is applied to the connector plug 9. This moves the rotatable member 30 rearwardly, thus compressing the urging means 42, and allowing the outwardly extending part 22 of the locking pin 20 to clear the turn in the slot 24. The connector plug 9 is rotated so that the outwardly extending part 22 of the locking pin 20 is opposite the forwardly extending section of the hook-shaped rearward end 50 of the slot 24, and is then released. The urging means 42 pushes the rotatable member 30 outwardly, and the outwardly extending part 22 of the locking pin 20 is seated in the forwardly extending section of the hookshaped rearward end 50 of the slot 24. This provides a very good mechanical connection between the bayonet connector 9 and the receptacle 18.
It should be understood, that While in the illustrated embodiment, the connector plug 9 is shown with one form of receptacle 18, other forms of receptacles can be used without departing from the invention.
Various other changes and modifications which will be obvious to those skilled in the art may be made in the above described bayonet connector without departing from the spirit or scope of the present invention. Various of the novel features of the invention are set forth in the appended claims.
1. An electrical bayonet type connector plug comprising an elongated body of resilient dielectric material having a generally cylindrical end portion, at least one contact member fixedly carried by said body and accessible to another contact member carried by a complementary receptacle, and a generally U-shaped locking pin formed of a hard material embedded in said end portion With the legs thereof extending radially outwardly, the leg closer to the face of said cylindrical end portion having an end part which extends outwardly from the dielectric material far enough to co-operate with a bayonet slot in the receptacle and the other leg being of sufiicient length such that the end thereof is approximately flush with the surface of said cylindrical end portion, the portion which connects the legs being spaced from the exterior of said end portion and irom the contact carried by said body.
2. An electrical bayonet type connector plug comprising an elongated flexible body of dielectric material including a generally cylindrical forward end portion,
the rearward end portion of said connector body being formed with a plurality of longitudinally extending raised ribs which provide means for gripping the plug, a plurality of female contact members located within said body and accessible to an equal number of complementary male contact members forming part of a complementary receptacle, a generally U-shaped metal locking pin embedded in said forward end portionwith the legs thereof extending radially outwardly, the leg closer to the face of said forward end portion having an end which extends outwardly from the dielectric material far enough to co-operate with a bayonet slot in-the receptacle, and the other leg being made of sufiicient length such that the end thereof is approximately flush with the surface of said forward end portion.
References Cited in the tile of this patent UNITED STATES PATENTS 1,158,578 Stearns Nov. 2, 1915 1,780,851 Strongson Nov. 4, 1930 2,704,356 Herterick Mar. 15, 1955 2,710,385 Sprigg June 7, 1955 2,833,997 Brown May 6, 1958 2,844,672 Sambonet July 22, 1958 2,947,966 Francis et a1. Aug. 2, 1960