Electrical Connection Jack

This invention relates to an electrical connection jack, and more particularly to an electrical connection jack into which a rotary plug is to be inserted.

A turn-table system electronic cooking range, for example, inserts a rod-like thermocouple into cooked beef to measure an internal temperature thereof to thereby automatically control a roasting condition of beef.

In such case, since the thermocouple rotates together with beef, it is problematical to connect a plug mounted to one end of thermocouple with a jack into which the plug is to be inserted.

Such connecting means includes, for example, the jack supported rotatably to the ceiling of a cooking room, in which at the upper end of jack is mounted two round electrodes conductive with internal segments, and ship-like contact segments of elasticity is mounted to the frame supporting the jack.

The plug is inserted into the jack to fetch a detection signal of thermocouple through the round electrode and contact segments in contact therewith.

Such conventional method rotates the jack in itself and disposes the strip-like contact segments perpendicularly to the rotary axis, thereby having created the problem in that a plug support portion inclusive of the jack is complicated in construction and becomes larger in the size. Also, since sliding caused by rotation of electrode and contact segments increases, an improvement in wear resistance at the rotary contact portion has been required.

An object of the invention is to provide an electrical connection jack into which a rotary plug is to be inserted and which has a plug support portion simple in construction and small-sized.

Another object of the invention is to provide an electrical connection jack improvable of the wear resistance of the portion in contact with the rotary plug.

This invention can support the rotary plug without rotating the jack itself, whereby the plug supporting portion is made simpler in construction and larger in the size than the conventional one of rotating the jack itself. Also, the use of oil impregnate metal in the contact portion with the rotating plug is improvable of wear resistance.

In brief, the present invention is characterized in that the electrical connection plug into which the rotary plug is inserted uses oil impregnate metal to at least a sleeve in contact with the trunk of the plug.

These and other objects of the invention will become more apparent in the detailed description and examples which follows.

FIG. 1 is a perspective exploded view of an embodiment of an electrical connection jack of the invention,

FIG. 2 is an illustration of a casing in FIG. 1 when viewed from a side of an opening insertable of contact segments,

FIG. 3 is an illustration of a mounting method of an oil impregnate metal chips to the contact segments.

FIG. 4 is a sectional view of the embodiment of the electrical connection plug when a rotary plug is inserted therein, and

FIG. 5 is a perspective exploded view of the plug using oil impregnate metal at the rotary contact portion.

An electrical connection plug shown in FIG. 1 includes a sleeve unit 100, a casing 200, contact segments 310 to 340 and a holder 400.

In the sleeve unit 100, reference numeral 110 designates a support plate bent in U-like shape. A tongue-like terminal 112 is provided at a front plate 111 at the holder 110, retainer segments 114 vertically projecting are formed at the utmost end corners of side plates 113 at the holder 110, and a fixing plate 115 provided at both sides with threaded through bores 116 are mounted to the front plate 111, the front plate 111 and fixing plate 115 providing plug insertion bores 117 respectively. A cylinder 118 is mounted concentrically with the insertion bores 117 and a sleeve 119 of oil impregnate metal is press-fitted into the cylinder 118.

The casing 200 is a bottomed box-like-shaped member open at the segment insertion side and molded integrally with insulating synthetic resin. A plug insertion bore 201 is bored at the wall of casing 200 abutting against the front plate 111 at the support plate 110, the abutting surface providing a shallow recess 202 to be fitted onto the front plate 111. Also, at both lateral side surfaces of casing 200 are provided shallow grooves to be fitted to the side plates 113 at the support plate 110 and extending lengthwise of casing 200, and bored elongate slots 204 for allowing an escape of the metal chip at the contact segment to be discussed below. On the upper and lower surfaces of casing 200 at the opening side are formed retaining projections 205 each having a slope downward toward the opening. Next, explanation will be given on the casing 200 in FIG. 2 when viewed from the contact segment insertion opening side. The opening at the contact segment insertion side has at four corners thereof hooked projecting ribs 206 each projecting at one end from each corner, the projecting ribs 206 extending at the other ends toward the inside of front plate 111. Between the projecting ribs 206 and the inner surfaces of four side plates at the casing 200, guide grooves 207 and 208, into which contact segments 310, 320, 330 and 340 are to be inserted, are formed respectively.

Referring again to FIG. 1, the contact segments 310, 320, 330 and 340 are formed by punching an elastic metal plate of, for example, phosphor bronze. Movable tongues 311, 321, 331 and 341 are formed of rectangular metal plates cut at the inner portion is U-like shape and raised respectively, especially the movable tongues 311 and 321 at the contact segments 310 and 320 are each cut and raised at the root near the front plate 202 of the casing 200. The respective contact segments 310 to 340 are provided at the edges at the opening sides with terminals 312, 322, 332 and 342 respectively, the movable tongues 311, 321, 331 and 341 being attached with oil impregnate metal chips 350 cylindrical and smaller in axial length respectively.

Next, explanation will be given on construction for mounting the oil impregnate metal chip in accordance with FIG. 3. For example, in the movable tongue 311, the fore end portion thereof is cut widthwise in furcation as shown. The oil impregnate metal chip 350 is provided at the outer periphery with smaller grooves 351 extending axially of chip 350 and opposite to each other, so that the furcate retaining projections 313 are elastically transformed to be fitted into an inner bore at the chip 350 and the cut edges opposite to the projections 313 are fitted into the small grooves 351 at the chip 350 respectively, thus mounting the oil impregnate metal chip 350 to the movable tongue 351 and holding it stably with respect to plug in or out and to rotation of the plug.

The holder 400, as shown in FIG. 1, is nearly U-like-shaped to sandwich both the upper and lower walls of casing 200 to thereby prevent each inserted contact segment from escaping from the casing 200, and molded integrally with insulating resin. A vertical plate 401 at the holder 400 is provided at both upper and lower ends with clipping brackets 402 and 403 having at the central portions engaging bores 404 engageable with the retaining projections 205 at the casing 200 respectively. The vertical plate 401 is provided at the central portion with a bore about equal in diameter to the plug, at the four corners with bores 405 into which the ends of projecting ribs 206 are fitted respectively, and at two diagonally opposite corners and the intermediate portions at two opposite sides with guide bores 406 corresponding to the terminals 312, 322, 332 and 342 at the contact segments 310 to 340 respectively.

The aforesaid components are assembled as follows:

The contact segments 310 and 320 are inserted into the casing 200 and in contact with the inner upper and lower surfaces thereof and those 330 and 340 into the casing 200 and in contact with the inner lateral side surfaces respectively. The holder 400 is fitted onto the opening at the casing 200 to project the terminals at the contact segments 310 to 340 outwardly from the holder 400 through guide bores 406 respectively and the retaining projections 205 at the casing 200 are fitted into the engaging bores 404 respectively, thereby retaining the holder 400 to the casing 200. Then, the sleeve unit 100 is mounted in the front of casing 200 to about against the front surface thereof, at which time retaining portions 114 at the sleeve unit 100 engage with the ends of grooves respectively, thereby retaining the sleeve unit 100 to the casing 200.

Next, explanation will be given on the state where the rotary plug is plugged into the electrical connection jack of the invention of reference to FIG. 4, in which the components identical with those in FIG. 1 are designated by the same reference numerals.

The rotating plug 500 comes into contact at it chip 510 with the oil impregnate metal chips 350 at the contact segments 310 and 320, the trunk 520 of plug 500 being supported in contact with a sleeve 119 and contacting with the oil impregnate metal chips 350 at the contact segments 330 and 340 (where the chips 350 are not shown). In this case, the terminals 112, 332 and 342 are short-circuited to be used as the ground terminals to ensure grounding of plug, the terminals 312 and 320 being short-circuited when in use.

Since the plug 500 inserted is subjected to an about equal urging force in every direction by the contact segments 310, 320, 330 and 340, the trunk 520 is prevented from being subjected to a deflection, thereby smoothing the rotation of plug.

The terminals 332 and 342 in the aforesaid embodiment, which are used together with the terminal 112 as the ground terminal, are not indispensably grounded, so that the terminal 112 only may be used as the ground terminal.

Also, the wear preventing means in the aforesaid embodiment is not limited to the use of oil impregnate metal in the contact portion of jack. For example, the oil impregnate metal may alternatively be used in the contact portion of plug so as to obtain the same effect. In such case, there is no need of using the oil impregnate metal to the contact portion at the jack.

Furthermore, various modified embodiments of contact segments or the like are adoptable other than the aforesaid embodiment. For example, it is of course possible to mount the metal chip to the movable tongue by welding.

While a preferred embodiment of the invention has been described using specific terms, such description is for illustrative purpose only, and it is to be understood that changes and variations may be made without departing from the spirit or scope of the following claims.