JP3276607B2 - Plug-in plug terminal - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plug terminal used for electrical connection, and is particularly suitable for connecting a concrete vibrator to a power supply.

[0002]

2. Description of the Related Art It is preferable that an insertion plug terminal and a power supply outlet terminal used for electrical connection be in close contact with each other at the time of fitting. Therefore, a structure as shown in FIG. 7 has been conventionally proposed. This is the plug terminal 52 of the power supply outlet terminal 51.
Four slits 54 extending in the axial direction are provided at equal intervals on a peripheral wall of the fitting hole 53 (so-called cross slit), and a ring spring 5
5 is attached so that the inner wall of the hole 53 is urged inward to achieve close contact with the plug terminal 52. The plug terminal 52 is provided with a slit 56 to facilitate the mounting in the hole 53.

[0003]

In the above prior art, the plug terminal 52 is plastically deformed by the influence of an external force in repeated use (particularly the force at the time of plug attachment / detachment), the slit 56 becomes narrow, and the power supply outlet is provided. Hole 5
3 was smaller than the inner diameter, and contact failure sometimes occurred (see FIG. 8) .

In particular, in a concrete vibrator using a three-phase power supply, all three plug terminals and outlet terminals need to be securely in contact with each other. This causes operation, which causes motor burnout and failure of the power supply unit.

[0005]

SUMMARY OF THE INVENTION The present invention provides a plug
In the terminal, the insertion part is cylindrical, and it is
A lit is provided and the inside of the insertion part is the same as the inside dimensions of the insertion part
A cylindrical core member with the outer dimensions of
The inside surface of the insertion part is slightly open to the extent that it can be deformed.
Forming a gap between the core member and the core member to narrow the slit.
Is formed to form the plug terminal .

[0006]

According to the present invention, the insertion portion is prevented from being deformed inward by the core member mounted in the hollow portion of the insertion portion. Then, open the insertion part outside within the elastically deformable range
The insertion part is pressed by the hole of the outlet and
Inserted into the hole of the outlet in a deformed state and pulled out
Will be restored to the open state when
Good contact conditions are obtained. Therefore, poor contact due to deformation of the insertion portion (narrowing of the slit) can be avoided, and a good contact state can be obtained even in repeated use and with an outlet without a cross slit.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIG. 1, a plug terminal A has a hollow cylindrical shape having a hemispherical tip, and has a mounting portion 1 at a base end and an insertion portion 2 at a tip end. A slit 3 having an open distal end is formed in the insertion portion 2, and the insertion portion 2 is elastically deformable in the vertical direction in FIG. In the drawing, reference numeral 4 denotes a terminal screwed to the end of the mounting portion 1, and reference numeral 5 denotes a spring pin for preventing the plug terminal A mounted on the terminal plate 6 from coming off (see FIG. 4).

The insertion portion 2 is plastically deformed by a small angle θ with respect to the center line in the vertical direction in the figure. The deformation angle θ is a range within which the insertion portion 2 can be restored to θ by elastic deformation when the insertion portion 2 is inserted into the hole of the outlet and the outer surface of the insertion portion 2 becomes parallel to the central axis and then pulled out from the outlet. .
For example, if the insertion portion is a plug terminal having a diameter of 8 mm, the vertical dimension H of the end portion is set to be about 8.5 mm.

A cylindrical core member 8 is mounted in the hollow portion 7 of the insertion portion 2. The core member 8 has the same cross-sectional dimension as the reference dimension of the hollow portion (the state where the deformation angle θ is not taken). That is, when the deformation angle θ is formed in the insertion portion 2, a gap is formed between the inner wall of the insertion portion 2 and the core member 8. When the insertion portion 2 is inserted into the hole of the outlet, the outer surface of the insertion portion 2 is in close contact with the hole of the outlet, and the inner surface is supported by the core member 8.

FIG. 3 is a sectional view showing a use state of the plug terminal A. Reference numeral 9 denotes a plug case, and 10 denotes a cable clamp.

As described above, according to this embodiment, the elastically deformable insertion portion 2 is vertically deformed by the small angle θ, so that when the insertion portion 2 is inserted into the hole of the outlet, And a reliable contact state is obtained. Then, when it is unplugged from the outlet, it is restored to the angle θ by elastic deformation. Further, since the inner wall of the insertion portion 2 is supported by the core member 8, even if the angle θ is gradually reduced by repeated use, the insertion portion 2 cannot be deformed inward. Therefore, the narrowing due to the deformation of the insertion portion 2 to the inside, which is a conventional problem, is prevented beforehand, and a poor contact is avoided.

In order to manufacture the plug terminal of this embodiment, a core member 8 is formed from the other end of a round bar having one end shaped into a hemisphere.
After forming a hollow portion 7 for mounting the same and forming a slit 3 having a constant width, the tip of the insertion portion 2 is opened moderately to obtain an angle θ by slight plastic deformation. Next, the core member 8 is inserted from the opening end of the hollow portion.

In the above embodiment, the core member 8 is inserted into the hollow portion 7 from the base side (terminal 4 side) of the plug terminal, and the core member 8 is inserted and assembled from the tip end side of the plug terminal. You may do so. Also, a core member
8 may be attached only to the tip of the insertion portion.

FIGS. 4 and 5 show a state in which a hollow portion 7 is drilled from the distal end side of the plug terminal A, and a rod-shaped core member 8 is press-fitted through a circular hole 13 formed at the distal end of the plug terminal .
Reference numeral 6 denotes a screw formed at the bottom of the hollow portion 7 of the plug terminal A and screwed with a rod-shaped core member 8 having a screw formed at the tip.

[0015]

According to the present invention, the inside of the insertion portion is supported by the core member, and inward deformation (narrowing) is prevented. That is, even if a crushing load is applied to the slit of the plug terminal, deformation is prevented by the core member, and poor contact with the power supply terminal of the power outlet is prevented. Therefore,
A good contact state can be obtained with a power supply terminal not provided with a cross slit, and troubles such as burnout of a motor and failure of a power supply device can be prevented. The plug terminal of the present invention is effective not only as a plug for a concrete vibrator but also as a power supply plug for a relatively large current electric device such as a welding machine in which troubles due to poor contact are likely to occur. However, the use as a small current plug is also included in the scope of the present invention.

[Brief description of the drawings]

FIG. 1 is a front sectional view of an embodiment of the present invention.

FIG. 2 is a side sectional view of the same.

FIG. 3 is a cross-sectional view showing the same use state.

FIG. 4 is a front sectional view of an embodiment in which a core member is press-fitted.

FIG. 5 is a side view of the same.

FIG. 6 is a front sectional view of an embodiment in which a core member is screwed.

FIG. 7 is a sectional view of a conventional example.

FIG. 8 is a front view showing a deformed state of a conventional plug terminal .
Front view

[Explanation of symbols]

 A Plug terminal 1 Mounting part 2 Insertion part 3 Slit 4 Terminal 5 Spring pin 6 Terminal plate 7 Hollow part 8 Core member 9 Plug case 10 Cable clamp 12 Spring slit 13 Hole

Continuation of the front page (72) Inventor Mitsuo Onodera 1-17-13 Hamamatsucho, Minato-ku, Tokyo Inside Exen Corporation (56) References JP-A-60-65487 (JP, A) Registered utility model 3024440 (JP) , U)

Claims (1)

(57) [Claims] In the plug terminal, the plug portion is
It has a cylindrical shape, and a slit is provided in the axial direction.
A core member is attached to the core member, and the core member has a cylindrical shape having an outer dimension equivalent to the inner dimension of the insertion portion.
The insertion portion is slightly opened outward, and the inner surface of the insertion portion and the core member are opened.
A gap within the elastic deformation limit of the insertion portion between the insertion plug terminal and the narrowing of the slit is prevented.