JPH0339888Y2 - - Google Patents

Description

[Detailed description of the invention] "Industrial application field" This invention applies to one or both ends of the curl cord connecting the telephone body and the handset, or the line cord connecting the telephone body and the wall terminal block. The present invention relates to a telephone plug provided. The plug is inserted into a jack provided on the mating side and held, and each core wire (insulated conductor) of the cord and the corresponding mating conductor are electrically connected to each other.

``Prior art'' Traditionally, this type of telephone plug was
No. 33941 "Electrical Connector" is proposed.
Examples are described in detail in the above document, so
Although repeated explanation will be omitted, the outline is as follows. That is, as shown in FIG. 7, a cord insertion hole is formed in one end surface of the plug main body 1, which is a substantially rectangular parallelepiped, and the core wire of the cord 2 is inserted into the cord insertion hole at a predetermined pitch, and the main body adjacent to the one end surface is inserted into the cord insertion hole at a predetermined pitch. A plurality of tangent grooves are formed parallel to each other on the surface of 1, corresponding to each of the core wires. A protrusion insertion hole is formed at the bottom of each contact piece groove so as to communicate with the cord insertion hole. A contact piece 3 shown in FIG. 8 is inserted into each contact groove, and its pair of sharp protrusions 3a are inserted into the core wire through the protrusion insertion hole to be electrically connected to each other.

"Problems with the Prior Art" When the plug provided at the end of the cord is inserted into the jack, the contact 4 of the jack comes into elastic contact with one side of the upper end surface 3b of the contact piece 3, as shown in FIG. A mutual electrical connection is made. However, the contact piece 3 is made by punching out a thin plate, and the metal surface of the punched surface is rough, so the contact resistance with the contact 4 varies widely, and the stability of the resistance value over a long period of time is difficult. Ta. In addition, in order to improve the stability of electrical contact, it would be preferable to partially apply gold plating to at least one side of the upper end surface that contacts contact 4, since the amount of plating would be small, but Since it is technically difficult to partially plate the cut surface, contact piece 3
The entire surface of the building had to be plated with gold, which caused economic problems.

Further, the contact pieces 3 are manufactured in a state in which a large number of pieces are connected as shown in FIG. When inserting the plugs into the contact grooves, it was necessary to cut the plugs at the points indicated by dotted lines in the same figure and insert them one by one, which made workability difficult.

The purpose of this invention is to eliminate these conventional drawbacks, eliminate the risk of variation in contact resistance or change over time due to roughness of the metal surface of the contact piece, and eliminate the need for a contact piece that makes contact with the jack contact. To provide a telephone plug which can be plated only in parts, which leads to reduction in cost, and which has good workability so that all the contact pieces necessary for the plug can be attached at the same time.

"Means for Solving the Problem" According to this invention, a cord insertion hole is formed in one end surface of the contact piece body, which is a substantially rectangular parallelepiped, and the cord core wires are inserted into the cord insertion hole at a predetermined pitch (interval). Ru. A plurality of contact grooves are formed parallel to each other in correspondence with each of the core wires on the surface of the main body adjacent to the one end surface, and an integrated contact piece insertion hole is formed in the bottom of each contact piece groove to correspond to the cord insertion hole. Communication is formed. An intermediate portion of a U-shaped contact piece is disposed in each of the contact piece grooves, and both legs thereof are inserted into the core wire through the pair of contact piece insertion holes to be electrically connected to each other, and the intermediate portion of the contact piece is A pair of claws are integrally formed that extend outward from both side edges of the contact piece groove and engage with the wall surface of the contact piece groove.

``Example'' As shown in FIG. 1, the contact piece 3 used in this invention has a substantially U-shaped outer shape, and has an intermediate portion 3d and a pair of legs bent and extended by approximately 90 degrees with a curvature from the intermediate portion 3d. 3f. A pair of claws 3g extend outward from both side edges of the intermediate portion 3d. This contact piece is made by punching out a thin band-shaped metal material, and a large number of contact pieces have their claws 3g connected to each other, and are chain-like parts arranged in parallel at intervals equal to the mutual spacing between the contact piece grooves of the plug. Manufactured as. A separating groove 3h having a V-shaped cross section is provided at the connecting portion of the claw 3g to facilitate later separation of the contact pieces, and a triangular portion with a sharp point is formed at the end of the leg portion 3f. As the triangular part approaches the tip, it becomes thinner and sharper. One curved surface of the contact piece 3 that contacts the contact is partially plated with gold, for example.

The plug main body 1 is made of a synthetic resin material, and as shown in FIG. 2, it has a substantially rectangular parallelepiped shape, and a cord insertion hole 1a extends deep into the interior from one end surface to near the opposite surface. The cord insertion hole 1a has a large cross section so that the cord can be inserted with the outer sheath halfway through, but from the middle, the core wire (also called an insulated conductor) is removed without the outer sheath.
The cross section is made small so that only the core wire (see FIG. 3) can be inserted, and a large number of linear guides 1b are formed in parallel to guide each core wire at a predetermined pitch. The cord insertion hole 1a has a small cross section and the guide 1b
The portion divided by is called the core wire insertion hole 1c.

Adjacent to the one end surface where the cord insertion hole is provided, a plurality of contact grooves 1d are formed in parallel in one half of the front surface in correspondence with each of the core wires, and a pair of contact grooves 1d are formed at the bottom of each contact groove. The contact piece insertion hole 1e is dug down and communicated with the core wire insertion hole 1c (of the cord insertion hole 1a). A right triangular prism-shaped cord retainer 1f is formed on the other half of the front surface of the main body 1, and one acute-angled side edge of the cord retainer 1f is connected to the main body 1 to form a thin connecting portion 1g. A communication hole 1i is drilled down between the cord restrainer 1f and the main body 1 around the periphery of the cord retainer 1f except for the connecting portion 1g, and is communicated with the cord insertion hole 1a. Cord restraint 1f
A protruding engagement piece 1 is located in the middle of the other acute-angled side edge of the
j is formed. As shown in Fig. 2F, insert the cord 2 into the cord insertion hole 1a, and
When the right-angled part of the cord is strongly pushed into the outer jacket of the cord, the engaging piece 1j engages with the corner part 1h of the main body 1 where the communication hole 1i and the cord insertion hole 1a intersect and becomes a stopper, and the cord 2 becomes a stopper. It is firmly held down by the 1st presser and will not slip out.

How to attach the contact piece 3 As a jig for attaching the contact piece 3 to the main body 1 of the plug, an assembly stand 8 as shown in FIG. 4 and a punch 9 as shown in FIG. 5 are used.

When the plug body 1 with a cord is attached and fixed to the assembly base 8, contact piece insertion slits 8a of approximately the same size are provided in parallel on the top surface facing each contact piece groove 1d, and these slits 8a and One guide groove 8b for guiding the plurality of chain-shaped contact pieces 3 is provided in the upper part of the grooves 8b in communication with each other. The chain-shaped contact pieces 3 are fed from the left side of the figure, and stop at a position where the claw 3g of the rightmost contact piece abuts against the inner wall of the mounting base 8. When the punch 9 is pushed downward with each tooth 9a facing the intermediate portion 3d of each contact piece 3 at intervals equal to the interval between the contact piece grooves 1d, that is, the predetermined pitch of the core wire, a chain-like contact is formed. Piece 3 is at point P shown in A in the same figure, and the contact claw 3g (see Fig. 1) is inserted into the separation groove 3h by the punch 9 and the edge of the side wall of the assembly base 8.
The contact piece is cut along the guide groove and pushed into the guide groove, and both leg portions 3f of the contact piece are inserted into the contact piece insertion slit 8a. A cutting blade 8c is formed at the bottom of the guide groove 8b to separate the contact pieces 3 along the separation groove 3h between the contact piece insertion slits 8a.
The chain-shaped contact piece 3 is pushed down by the teeth 9a of the punch and cut by the cutting blade 8c. When the punch 9 is further pushed down, as shown in Fig. 6,
The claw 3g is bent upward from both end edges of the contact piece 3, is pushed downward into the contact piece insertion slit 8a, and the ends of both leg parts 3f of the contact piece are inserted into the contact piece groove 1 of the plug.
d (Fig. 4C). When the punch 9 is pushed all the way down, the sharp tips of the legs 3f break through the coating of the core wire and pierce the internal metal conductor, creating an electrical connection (FIG. 4D). In this state, the claw 3g of the contact piece engages with the wall surface of the contact piece groove 1d and does not come off easily.

Returning to FIG. 2, a plate-shaped locking lever 1k extends obliquely from the back wall of the main body 1 on the distal end side of the core wire insertion hole 1c at an acute angle with the longitudinal direction of the cord insertion hole. The first small section of the locking lever 1k branching from the main body 1 is a thin walled portion 1l, and the locking lever 1k can be elastically bent toward the main body in this section. In other words, this small section is considered flexible. The other sections of the lever are made thicker,
Not flexible. The thick part is narrowed at both shoulders by a pair of steps 1 m in the middle. When the plug body 1 is inserted into a jack (not shown), locking pieces provided on the jack engage with both stepped portions 1m to prevent it from coming off. In this state, as shown in FIG. 2F, the contact 10 in the jack is
The main body 1 of the plug and the jack are mechanically and electrically connected. To remove the plug body 1, push the free end of the locking lever 1k toward the main body, the thin wall portion 1l will be bent, and both stepped portions 1m will slide toward the plug body, allowing them to connect with the locking piece of the jack. Easily disengaged.

``Effects of the invention'' According to this invention, the part of the contact piece that comes into contact with the jack contact is not a punched surface using a press as in the past, but a plate surface of the metal material, so there is no roughness on the material surface. Therefore, variations in electrical contact and stability are not a problem. Furthermore, since it is easy to partially plate the vicinity of the plate surface that comes into contact with the contact, the cost required for plating can be reduced compared to the conventional method. It is easy to manufacture contact pieces by connecting a large number of contact pieces in a chain through claws at intervals equal to the interval between the contact grooves of the plug body (equal to the predetermined pitch of the core wire) and parallel to each other. All the necessary contact pieces can be attached to the plug at the same time using a simple assembly jig using the contact pieces, and the workability of plug assembly can be significantly improved.

[Brief explanation of the drawing]

Figures 1A, B, and C are front views, right side views, and bottom views of the chained contact pieces used in this invention, and Figures 2A, B, C, D, E, and F are respectively Front view, left side view, right side view, bottom view, A-A sectional view and B-B of the telephone plug of this invention, respectively.
3 is a perspective view showing an example of a telephone cord, and FIG. 4 is an explanation of the process of attaching the contact piece 3 of FIG. 1 to the plug body 1 of FIG. 2 using an assembly jig. FIG. 5 is a perspective view of a punch used as one of the contact piece assembling jigs; FIG.
The figure is a perspective view of the contact piece 3 of Figure 1 with the separation groove cut by the assembly jig and the claw bent, Figure 7 is a perspective view of a conventional telephone plug, and Figure 8 is the figure 7. FIG. 9 is a front view of the contact pieces 3 of the telephone plug of FIG. 8 connected in a chain.

Claims (1)

[Claims for Utility Model Registration] A cord insertion hole is formed in one end surface of the substantially rectangular parallelepiped main body, a cord core wire is inserted into the cord insertion hole at a predetermined pitch, and each of the above-mentioned parts is formed on the surface of the main body adjacent to the one end surface. A plurality of contact piece grooves are formed parallel to each other in correspondence with the core wires, a pair of contact piece insertion holes are formed at the bottom of each of the contact piece grooves to communicate with the cord insertion hole, and a U-shape is formed in each of the contact piece grooves. A middle part of a shaped contact piece is disposed, both legs of which are inserted into the core wire through the pair of contact piece insertion holes to be electrically connected to each other, and extend outward from both side edges of the middle part of the contact piece. ,
A telephone plug that is integrally formed with a pair of claws that engage with the wall of the contact groove.