JP2005235400A - Terminal device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To downsize a terminal device which is prevented from falling by a loosened terminal screw pressed against a charging protection cover with a return spring, and to improve its wiring quality. <P>SOLUTION: In the terminal device in which terminal screws 4 with a washer 3 each are screwed into each screw hole 12 of terminal plates 2 fixed to a base stand 1, with the terminal screws 4 biased toward an axis direction and pressed against a charging protection cover 5 mounted on the base stand 1 in a state slipped out of the terminal plates 2 by return springs 8 inserted between the base stand 1 and the cover 5, the return springs 8 are made engaged with axis parts of the terminal screws 4 through arms 10. Since there is no need of providing the washers 3 with engagement parts with the return springs 8, no more space is needed for the washers 3 to be enlarged, nor is hooked the engagement parts of the washers 3 by the base stand 1 to make fastening of the terminal screws 4 insufficient. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

    The present invention relates to a terminal device mainly used for a control instrument such as an indicator lamp or a push button switch.

  FIG. 5 is a longitudinal sectional view showing a conventional general terminal device of this type. In FIG. 5, a terminal screw 4 having a washer 3 is screwed onto a terminal plate 2 fixed to an insulating base 1, and the terminal screw 4 is loosened between the terminal plate 2 and the washer 3. A single wire or a crimp terminal that is not connected is sandwiched, and the terminal screw 4 is tightened to connect the wiring. The base 1 is provided with a charge protection cover 5 that prevents a finger from touching the charging unit. The lower part of the base 1 is connected to a main body of a control instrument such as an illumination part of an indicator lamp and a contact part of a push button switch (not shown). This terminal device has a problem that when the terminal screw 4 is loosened, the terminal screw 4 easily falls off the terminal plate 2 and is lost.

Therefore, a terminal device has been developed in which a return spring is provided to urge the terminal screw in the axial direction, and the terminal screw pulled out of the terminal plate with this return spring is pressed against the charge protection cover mounted on the base. Such terminal devices are described in Patent Document 1 and Patent Document 2.
JP-A-9-129277 JP-A-9-180790

  In the terminal device disclosed in Patent Document 1 or Patent Document 2, an engagement portion for engaging a return spring with a washer of a terminal screw is integrally bent, and the return spring is applied to the engagement portion to attach the terminal screw. It is fast. However, the terminal device using such a special washer has the following problems.

  First, the place where the engaging portion of the washer that engages the return spring protrudes to the side is taken up, resulting in an increase in the size of the terminal device. Next, by adding a special shape to the washer, the assembling direction of the terminal screw is limited, and the terminal screw needs to be aligned when the terminal device is assembled, so that the assembling workability is deteriorated. In addition, when the terminal screw is tightened, the washer engaging portion is in sliding contact with the guide surface of the base, so if the terminal screw becomes slanted when a single wire is wired or the insertion angle of the driver is inclined, the washer The engaging portion of the base plate is caught on the guide surface of the base, and the friction is increased so that a necessary tightening force may not be obtained.

  Accordingly, an object of the present invention is to reduce the size of the terminal device and improve the assembly workability and the wiring quality in the terminal device in which the loosened terminal screw is pressed against the charging protection cover with a return spring to prevent the falling off. The goal is to improve.

  In order to solve the above-described problems, the present invention is configured such that a terminal screw having a washer is screwed into a screw hole of a terminal plate fixed to a base, and a return spring is inserted between the terminal screw and the base. In the terminal device in which the terminal screw urged in the axial direction by the return spring is held by being pressed against the charge protection cover mounted on the base in a state of being pulled out from the terminal plate. The spring is engaged with the shaft portion of the terminal screw (claim 1). According to the invention of claim 1, by directly engaging the return spring with the shaft portion of the terminal screw, it is not necessary to provide the washer with an engagement portion with the return spring, and the required space of the washer is increased. The engaging part does not get caught on the base.

  In the invention of claim 1, a compression coil spring is used for the return spring, and an arm composed of a linear portion projecting laterally and a curved portion at the tip thereof is provided on the return spring, and the curved portion of the arm is It is good to fit in the axial part of a terminal screw (Claim 2). According to the second aspect of the present invention, since the direction of the terminal screw can be freely changed with respect to the return spring, the assembling workability is improved without limiting the direction of assembling the terminal screw.

  According to this invention, it is not necessary to make the washer special, the structure of the terminal screw is simplified, the terminal device is miniaturized, and it is not necessary to worry about the assembly direction of the terminal screw. It will be easy. Further, even if the terminal screw is inclined, the washer is not caught on the base, and a stable tightening force can be obtained. Furthermore, since standard terminal screws can be used as they are, there is no problem of an increase in types of parts or an increase in inventory due to the use of dedicated terminal screws.

  Hereinafter, an embodiment of the present invention in a terminal device for a square indicator lamp will be described. Here, FIG. 1 is an exploded perspective view of the terminal device, FIG. 2 is a longitudinal sectional view of the assembled terminal device, FIG. 2 (A) is a state in which the terminal screw is tightened, and FIG. 2 (B) is a loosened terminal screw. FIG. 3 is an enlarged side view of the terminal screw in FIG. In addition, the same code | symbol shall be used for the part corresponding to a prior art example. In FIG. 1 to FIG. 3, a terminal board 2 is fixed to a rectangular base 1 by fitting in two diagonal positions, and a terminal having a square washer 3 attached to the neck of the terminal board 2. The screw 4 is screwed. 6 is a spring washer. A square charging protection cover 5 is attached to the base 1 through engagement via a leg portion 5a. A work hole 7 is formed in the upper surface of the charge protection cover 5 so as to face the terminal screw 4.

  Here, two cylindrical spaces 9 for accommodating return springs 8 for urging the two terminal screws 4 are provided at two positions in the upright prismatic part at the center of the base 1. The return spring 8 is formed of a compression coil spring, and an arm 10 including a linear portion 10a projecting laterally and a curved portion 10b at the tip thereof is provided at the upper end portion of FIG. As shown in FIG. 3, the return spring 8 has the curved portion 10 b of the arm 10 fitted into the shaft portion of the terminal screw 4 immediately below the washer 3 and engages with the terminal screw 4 as shown.

  In FIG. 1, the return spring 8 engaged with the terminal screw 4 is inserted into the cylindrical space 9 of the base 1, and its lower end is brought into contact with the bottom surface of the cylindrical space 9. Here, a slit 11 through which the straight portion 10 a of the arm 10 passes is provided on the side wall on the terminal screw side of each cylindrical space 9 along the axial direction of the cylindrical space 9. Therefore, when the return spring 8 is inserted into the cylindrical space 9, the straight portion 10 a of the arm 10 is simultaneously inserted into the slit 11. Next, the terminal screw 4 is screwed into the screw hole 12 of the terminal plate 2 that has already been fitted and fixed to the base 1. Thereby, the return spring 8 is compressed and biases the terminal screw 4 in the axial direction. Finally, the charging protection cover 5 is attached to the base 1. FIG. 2 shows the terminal device after such assembly work. A display lamp body (not shown) is connected to the lower portion of the base 1.

  In the terminal device shown in FIG. 2, when connecting a single wire, a screwdriver is inserted through the work hole 7, and the terminal screw 4 is loosened to make a necessary gap between the terminal plate 2 and the washer 3. On the other hand, when connecting an electric wire using a crimping terminal, the terminal screw 4 is completely loosened and pulled out from the terminal plate 2. As shown in FIG. The spring force of the return spring 8 is received and pressed against the charge protection cover 5 via the washer 3 and held as shown. Thereby, the terminal screw 4 does not fall off from the terminal device. In addition, the charging part protective cover 5 is formed with a rectangular tubular part 5 b that guides the vertical movement of the washer 3.

  When the electric wire is tightened, the terminal screw 4 is screwed in while compressing the return spring 8. At that time, the return spring 8 is surrounded by the wall surface of the cylindrical space 9 except for the slit 11. It will not bend. Further, since the arm 10 of the return spring 8 moves while being guided by the slit 11, it does not sway left and right, and serves to correct the inclination (falling) of the terminal screw 4. As a means for preventing the return spring 8 from bending, an upright shaft that passes through the center of the return spring 4 may be provided. Further, the return spring 8 may be engaged between the head of the terminal screw 4 and the spring washer 6 as shown in FIG.

  In the terminal device described above, the return spring 8 is directly engaged with the shaft portion of the terminal screw 4, and the washer 3 is not provided with an engagement portion with the return spring 8. Therefore, the required space is not enlarged by the lateral extension of the washer 3, and the engaging portion of the washer 3 is not caught by the base 1 and the electric wire is not sufficiently tightened. Further, since the direction of the terminal screw 4 can be freely changed with respect to the return spring 8, the direction of assembly of the terminal screw 4 to the base 1 is not limited, and the assembling work is easy. Further, the terminal screw 4 can be a standard product as it is, so that the cost is reduced and the parts management is also simplified.

It is a disassembled perspective view of the terminal device which shows embodiment of this invention. It is a longitudinal cross-sectional view of the terminal device of FIG. 1, (A) is the state which tightened the terminal screw, (B) is the state which loosened the terminal screw. FIG. 3 is an enlarged side view of a terminal screw in FIG. 2. It is an enlarged side view of the terminal screw which engaged the return spring between the head of the terminal screw and the spring washer. It is a longitudinal cross-sectional view which shows the conventional terminal device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Base 2 Terminal board 3 Washer 4 Terminal screw 5 Charging part protective cover 8 Return spring 10 Arm 10a Linear part 10b Curved part

Claims (2)

A terminal screw having a washer is screwed into the screw hole of the terminal plate fixed to the base, and a return spring is inserted between the terminal screw and the base, and the return spring is urged in the axial direction. In the terminal device, the terminal screw is held by being pressed against the charge protection cover attached to the base in a state of being pulled out from the terminal plate.
A terminal device, wherein the return spring is engaged with a shaft portion of the terminal screw. A compression coil spring is used as the return spring, and an arm composed of a linear portion projecting in the lateral direction and a curved portion at the tip thereof is provided on the return spring, and the curved portion is fitted into the shaft portion of the terminal screw. The terminal device according to claim 1.

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