JP4232964B2 - Screw terminal structure and indicator - Google Patents

Description

  The present invention relates to a screw terminal structure that relays electric power or an electric signal to, for example, an electrical device such as a switchboard or a monitoring panel of a nuclear power plant, a thermal power plant, and a substation, and an indicator lamp and a rotation using the screw terminal The present invention relates to an indicator such as an expression indicator.

  Using this type of conventional rotary display as an electrical device, it is possible to monitor the operating state of various power devices depending on whether the bar-shaped flag is oriented horizontally or vertically. . A terminal structure for relaying electric power or electric signals to the rotary display will be described.

  10 is an exploded perspective view showing a terminal structure of a conventional rotary display, and FIG. 11 is a front view of the terminal structure of FIG.

  10 and 11, the terminal structure 100 includes three terminals 101, a socket 102 having an outer diameter of 30 mm in which the three terminals 101 are disposed, and a stop ring 103 for preventing the terminal 101 from being removed from the socket 102. And have.

  The terminal 101 is formed by cutting a metal bar having a hexagonal cross section (for example, a brass material) by stepping the tip portion with two types of diameters and, for example, M3.5 on the end surface opposite to the tip portion. The female thread is processed.

  The socket 102 is resin-molded with a highly insulating engineering plastic, forms a wall portion 104 for insulation between the three terminals 101, and includes a stepped portion of each terminal 101. A through hole through which the smallest diameter portion passes and a hexagonal recess that can accommodate an outer shape hexagonal portion having the same central axis of the through hole up to a predetermined height are formed.

  The stop ring 103 is pressed into the tip portion (minimum diameter portion) of the terminal 101 to prevent the terminal 101 from coming off from the socket 102.

  With the above configuration, when the conventional terminal structure 100 is assembled, first, the stepped portion of the terminal 101 is passed through the through hole of the socket 102 and the outer hexagonal portion is press-fitted into the hexagonal recess to a predetermined height.

  Next, the stop ring 103 is press-fitted into the tip portion (minimum diameter portion) protruding from the opposite side of the socket 102 from the press-fitting side.

  As a result, the terminal 101 does not come out of the socket 102 and is also prevented from rotating at the hexagonal recess of the socket 102.

Such a conventional terminal structure 100 can be used for various displays such as a magnetic reversal display as disclosed in Patent Document 1 in addition to the above-described indicator lamp and magnetic rotary display.
JP-A-8-185131

  In the above conventional display device, the outer diameter is φ30 mm, but there is a tendency to reduce the mounting pitch on the panel surface to make it a high-density arrangement, and accordingly, downsizing is unavoidable, and the outer diameter of the display device is also increased. There is a demand for φ20 mm. In this case, since the thickness of the wiring and the size of the mounting screw remain as M3.5 terminal screws with a 2 sq electric wire, 2 sq crimping is required when the outside diameter of the display is greatly reduced from φ30 mm to φ20 mm. Considering the dimensional relationship of the layout of the three terminals 101 to which the terminals are fastened, it is very strict to arrange the three terminals 101 within an outer diameter of φ20 mm, and the tensile strength due to wiring, the tightening strength of the terminal screws, etc. There was a problem that it was necessary to ensure the strength of the terminal side.

  Further, in the assembly process of the conventional terminal structure 100, there are a press-fitting process of the terminal 101 into the socket 102, a press-fitting process of the stop ring 103 into the terminal 101, etc. However, problems due to press fitting such as insufficient holding may occur.

  The present invention solves the above-mentioned conventional problems, ensuring the strength on the terminal side, such as the tensile strength due to wiring and the tightening strength of the terminal screw, and eliminates the press-fitting process of parts, greatly reducing the man-hours for assembling the terminal part. An object of the present invention is to provide a screw terminal structure that can be used and a display using the screw terminal structure.

The screw terminal structure of the present invention is a screw terminal structure that relays electric power or an electric signal, and has a plurality of U-shaped screw terminals having four corners at the periphery of a screw hole, and the screw terminals are fitted therein. And an insulating member that holds the four corners so as to restrict the movement of the screw terminal in a direction along a plane including the four corners, and the four corners are fitted to predetermined positions of the insulating member. The screw terminal is fitted with a single touch so that the open side of the U-shaped screw terminal is widened and is held by a predetermined portion of the insulating member , thereby achieving the above object. .

  Preferably, the screw terminal in the screw terminal structure of the present invention is formed by pressing a copper alloy material having spring properties.

  Further preferably, the screw terminal in the screw terminal structure of the present invention includes a washer member in which four corners are formed at a peripheral portion of the screw hole, and a width is reduced on one side of the washer member and bent on one side. A continuous member that is connected to the washer member and a fixing member that is further bent to one side and connected to the continuous member are formed in a U-shape in a side view.

  Further preferably, the connecting member in the screw terminal structure of the present invention is formed with a fixing hole or a fixing protrusion for preventing displacement, and the insulating member side position corresponding to the fixing hole or the fixing protrusion is provided with the fixing hole or the fixing protrusion. Protrusions or recesses that can be fitted into the fixing holes or the fixing protrusions are formed.

  Further preferably, an M3.5 female screw is formed in the screw hole in the screw terminal structure of the present invention, and the outer diameter of the insulating member is φ20 mm.

  The display of the present invention enables display driving by relaying electric power or an electric signal using the screw terminal structure according to any one of claims 1 to 5, thereby achieving the above object. .

  In the display device of the present invention.

  With the above configuration, the operation of the present invention will be described below.

  In the present invention, the screw terminal (terminal fitting) has four corners (four corners) in the vicinity of the periphery of the screw hole, and the terminal socket as the insulating member extends along a plane including the four corners. Since the four corners of the screw terminal are held so as to prevent the screw terminal from moving in the opposite direction, the strength on the terminal side such as the tensile strength due to wiring and the tightening strength of the terminal screw is ensured. In addition, since the fulcrum for fixing the screw terminal is provided at a position (four corners) close to the point where the stress is generated (attachment position of the crimp terminal), it is difficult for the terminal socket to fall off due to deformation of the screw terminal.

  In addition, the screw terminal has a U-shape when viewed from the side, and a copper alloy material having a spring property is formed by pressing, so the open portion side of the U-shaped screw terminal is widened and a predetermined portion of the terminal socket is formed. It is possible to fit with one touch so as to hug. For this reason, the press-fitting process of parts (or caulking process, bonding process, etc.) is eliminated as in the prior art, and the man-hours for assembling the screw terminal are greatly reduced. In addition, since the screw terminals are formed by press working, instability of quality and high cost due to conventional cutting work are also eliminated.

  In addition to this, a fixing hole or fixing protrusion for preventing displacement is formed in the connecting member of the screw terminal, and the fixing hole or fixing is fixed at a position on the insulating member side corresponding to the fixing hole or fixing protrusion. If the protrusions or recesses that can be fitted to the protrusions are formed, the screw terminal insertion position does not shift with respect to the terminal socket. The terminal side strength such as the terminal screw tightening strength can be further secured.

  Further, when the screw hole is provided with a relatively large M3.5 female screw and the outer diameter of the insulating member is as small as φ20 mm, the effect of securing the terminal strength of the present invention becomes remarkable.

  As described above, according to the present invention, the four corners formed at the peripheral edge of the screw hole of the U-shaped screw terminal in a side view can be fitted into a predetermined position of the insulating member and integrated with one touch. In addition to securing the strength on the terminal side, such as the tensile strength of the screw and the tightening strength of the terminal screws, the process of assembling the terminal part can be greatly reduced by eliminating the component press-fitting process.

  Embodiments of a screw terminal structure and a display using the same according to the present invention will be described below with reference to the drawings.

  1 is a front view showing an exploded structure of a main part of a screw terminal of a display according to an embodiment of the present invention, FIG. 2 is a partial side view of the display including the screw terminal portion of FIG. 1, and FIG. FIG. 4 is a perspective view of the rear portion of the display unit including the screw terminal portion of FIG. 1 as viewed from the lower rear side, and FIG. 4 is a perspective view of the rear portion of the display unit including the screw terminal portion of FIG.

  1 to 4, a screw terminal 1 (screw terminal structure) includes three screw terminals 2 and a terminal socket 3 having an outer diameter of φ20 mm as an insulating member on which the three screw terminals 2 are arranged (laid out). And have.

  The screw terminal 2 has a washer member 21 in which an M3.5 female screw (screw hole 4) is formed in the center part in a burring-processed pilot hole, and a width is reduced on one side of the washer member 21 on one side. The connecting member 22 bent in a row and the fixing member 23 having the same width as that of the connecting member 22 and further bent in one side are formed in a substantially U shape. This screw terminal 2 is formed by pressing a copper alloy plate or strip having a spring property into a predetermined shape by pressing, and is plated with nickel, tin or silver as a surface treatment.

  The washer member 21 has a shape (notches a and b) in which four corners (four corners) of a quadrilateral shape are cut out by a predetermined dimension. In other words, the washer member 21 has a quadrangular shape. The edge c of the tip of one side protrudes by a predetermined width at the center, and the opposite edge d (bending part) opposite to the protruding edge c is also protruded by a predetermined width at the center. It is bent at an angle of 90 degrees. In this case, the washer member 21 is formed with four corners (virtual quadrangular four corners; four corners) in the vicinity of the peripheral edge of the screw hole 4.

  The connecting member 22 has one end connected to the washer member 21 at an angle of 90 degrees, and the other end connected to the fixing member 23 at an angle of 90 degrees. The washer member 21 and the fixing member 23 are connected to each other. Are connected. The connecting member 22 is bent so as to have a stepped portion e that drops by one step in the middle. A cylindrical protective cover (not shown) is disposed outside the stepped portion e, and the outer peripheral surface of the protective cover is substantially flush with the outer surface of the connecting member 22 connected to the stepped portion e. A stepped portion e is formed as described above.

  The fixing member 23 has a rectangular outer shape and a central hole f formed at the center, and is disposed opposite the washer member 21 so as to hold a predetermined portion of the terminal socket 3 between the washer member 21 and the fixing member 23. It has become. The corner of the front end portion of the fixing member 23 is rounded to facilitate insertion of the terminal socket 3 into a predetermined position. Further, the fixing member 23 and the washer member 21 are arranged to face each other so that the central hole f of the fixing member 23 and the screw hole 4 of the washer member 21 are on the same axis.

  The terminal socket 3 is resin-molded into a predetermined shape using engineering plastics with high strength and insulation properties, in order to achieve insulation between each of the three screw terminals 2 in total, two on the upper side and one on the lower side. Recesses 32 (or receiving portions) in which the respective screw terminals 2 are respectively fitted in the respective areas in which the T-shaped wall portions 31 reverse to the front view are formed as ribs and the spaces between the screw terminals 2 are insulated by the wall portions 31. ) Is formed. In the recess 32 (or the receiving portion), the movement of the screw terminal 2 is restricted in a direction along a plane including the four corners (virtual quadrangular four corners; four corners) of the washer member 21 of each screw terminal 2. As described above, a holding part g for holding the four corners is provided. In addition, two rail-shaped tapered guide portions 33 are formed in the terminal socket 3 so that the rectangular fixing member 23 can be easily inserted. Further, the terminal socket 3 is formed with a recess into which the protruding end edge c (the tip protruding portion of the washer member 21 of the screw terminal 2) is fitted. Further, a terminal cover can be attached to the rear side of the terminal socket 3.

  With the above configuration, when the screw terminal 2 is assembled into the terminal socket 3 to assemble the screw terminal 1, first, the washer member 21 of the screw terminal 2 is fitted into the holding portions g at the four corners of the recess 32, and then the screw terminal 2 is assembled. 2 is guided by the taper-shaped guide portion 33 of the terminal socket 3, and the U-shaped open portion of the screw terminal 2 is widened by the spring property of the screw terminal 2, so that a predetermined portion of the terminal socket 3 The screw terminal 2 can be incorporated into the terminal socket 3 with a single touch so as to hold it.

  In this way, there is no press-fitting process as in the prior art, and the screw terminal 2 is fitted into the terminal socket 3 with one touch to assemble the screw terminal 1, so that the assembly man-hours of the terminal portion can be greatly reduced and the assembly is performed. In terms of quality, there is no press-fitting failure such as part dropping.

  In addition, the outer diameter of the display has been reduced from φ30 mm to φ20 mm, the wire thickness and mounting screw size are 2 sq, using M3.5 terminal screws as they are, and screw terminals 2 on the outside of the display Even if the terminal screws 2 are strongly pulled by the electric wires or the tightening strength of the terminal screws 2 is strong, the screw terminals 2 are pulled outside the display because the four corners of the washer member 21 of each screw terminal 2 are held by the holding portions g. The screw terminal 2 does not fall out and the screw terminal 2 does not tilt, and the position holding strength of the screw terminal 2 can be sufficiently secured. For this reason, it is not necessary to bear a part of the position holding strength on a cylindrical protective cover (not shown) for protecting the inside of the display. Thereby, when the outer diameter of the display is reduced from φ30 mm to φ20 mm, the thickness of the cylindrical protective cover can be made as thin as possible. Thus, since it is not necessary to bear the position holding strength with the cylindrical protective cover, the number of parts can be reduced when it is not necessary to attach the cylindrical protective cover to the display.

  Here, for comparison with the present embodiment, in the case of the terminal socket 3A without the holding portions g holding the two corners on the outer peripheral side among the four corners of the washer member 21 of each screw terminal 2, The screw terminal 1A as shown in FIGS. 5 to 7 was used to examine the removal strength in the direction opposite to the direction in which the screw terminal 2 was assembled into the terminal socket 3A.

  As shown in FIG. 5, first, the screw terminal 2 is moved in the direction of the arrow A and is fitted so as to hold a predetermined portion of the terminal socket 3 </ b> A by the spring property of the screw terminal 2 with one touch. At this time, the screw terminal 2 is held by being held by a predetermined portion of the terminal socket 3A due to its springiness.

  Next, the compatible crimp terminal 5 attached by caulking a 2 sq electric wire was attached to the screw hole 4 of the screw terminal 2 by fastening with an M3.5 pan screw 6. Further, when the crimping terminal 5 is pulled with a predetermined load (0.8 N; a load corresponding to the standard tightening torque of M3.5) in the direction of the arrow B (outside of the display) together with the electric wire, as shown in FIG. The screw terminal 2 has come out to the outside. FIG. 7 is a perspective view showing a state at this time, that is, a state in which the crimp terminal 5 is removed after the screw terminal 2 is pulled out to the outside.

  In this case, in the comparative example, in order to prevent the screw terminal 2 from coming out, the thickness of the cylindrical protective cover is required to be 1.5 mm in consideration of the safety level. Then, even if there is no cylindrical protective cover, there is no problem at all (the screw terminal 2 cannot be removed), and the thickness of the protective cover may be 1 mm or less. In short, as the thickness of the cylindrical protective cover is reduced, the effective space for the terminal layout is expanded and the degree of freedom of the layout is increased.

  In addition to the above embodiment, the screw terminal 2B and the terminal socket 3B in FIGS. 8 and 9 may be configured in order to further improve the strength of the screw terminal 2 to the outside. That is, a fixing hole 24B is formed at the center of the connecting member 22B of the screw terminal 2B, and when the screw terminal 2B is fitted into the terminal socket 3B, the terminal socket 3B corresponding to the fixing hole 24B is semicircular or A protrusion 34B such as a columnar shape may be formed. As the screw terminal 2B is less likely to be displaced with respect to the terminal socket 3B due to the fitting between the fixing hole 24B and the protrusion 34B, the strength of the screw terminal 2 to the outside is improved and the deformation of the screw terminal 2 is also suppressed. Can be done. Or, conversely, a fixed protrusion (not shown) for preventing displacement is formed on the connecting member 22, and the fixed protrusion is fitted at a position on the terminal socket side corresponding to the fixed protrusion. A recess (not shown) that can be combined may be formed.

  As mentioned above, although this invention has been illustrated using preferable embodiment of this invention, this invention should not be limited and limited to this embodiment. It is understood that the scope of the present invention should be construed only by the claims. It is understood that those skilled in the art can implement an equivalent range from the description of specific preferred embodiments of the present invention based on the description of the present invention and common general technical knowledge. Patents, patent applications, and documents cited herein should be incorporated by reference in their entirety, as if the contents themselves were specifically described herein. Understood.

  The present invention relates to, for example, a screw terminal mounting structure such as a power supply part of an electric device used in a switchboard or a monitoring panel of a nuclear power plant, a thermal power plant, and a substation, and an indicator lamp or a rotary display using the same. In the field of display devices such as display devices, the strength on the terminal side, such as the tensile strength due to wiring and the tightening strength of terminal screws, is ensured, and the process of assembling the terminal portion is greatly reduced by eliminating the component press-fitting process.

It is a front view which shows the principal part decomposition | disassembly structure of the screw terminal of the indicator which concerns on embodiment of this invention. FIG. 2 is a partial side view of an indicator including the screw terminal portion of FIG. 1. It is the perspective view which looked at the indicator rear part containing the screw terminal part of FIG. 1 from back lower side. It is the perspective view which looked at the indicator rear part containing the screw terminal part of Drawing 1 from the indicator lower part. It is a front view which shows the comparative example with respect to the screw terminal of FIG. FIG. 6 is a side view showing a state in which the screw terminal is pulled out to the outside in the comparative example of FIG. 5. It is a perspective view which shows the state which removed the crimp terminal after the screw terminal came out outside like FIG. It is the perspective view which looked at the indicator rear part containing the screw terminal part concerning other embodiments of the present invention from the indicator lower side. It is the perspective view which looked at the indicator rear part containing the screw terminal part concerning other embodiments of the present invention from the back lower side. It is a disassembled perspective view which shows the screw terminal structure of the conventional magnetic rotation type indicator. It is a front view of the screw terminal structure of FIG.

Explanation of symbols

1,1B screw terminal 2,2B screw terminal 21 washer member 22,22B connecting member 23 fixing member 24B fixing hole 3,3B terminal socket (insulating member)
31 Wall part 32 Concave part 33 Tapered guide part 34B Protrusion part g Holding part

Claims (6)

In the structure of a screw terminal that relays electric power or electrical signals,
A plurality of U-shaped screw terminals having four corners at the periphery of the screw hole and the screw terminals are fitted, and the movement of the screw terminals is regulated in a direction along the surface including the four corners. An insulating member that holds the four corners ,
The four corners are fitted to predetermined positions of the insulating member, and the screw terminals are opened with one touch so that the open side of the U-shaped screw terminal is widened and is held by a predetermined portion of the insulating member. Screw terminal structure to be fitted .   The screw terminal structure according to claim 1, wherein the screw terminal is formed by pressing a copper alloy material having a spring property.   The screw terminal includes a washer member having four corners formed at the peripheral edge of the screw hole, and a continuous member connected to the washer member with a width reduced to one side of the washer member and bent to one side. The screw terminal structure according to claim 1 or 2, wherein the installation member and a fixing member that is further bent to one side and is connected to the connection member are formed in a U-shape when viewed from the side.   The connecting member is formed with a fixing hole or a fixing protrusion for preventing displacement, and can be fitted to the fixing hole or the fixing protrusion at a position on the insulating member side corresponding to the fixing hole or the fixing protrusion. The screw terminal structure according to claim 3, wherein a protruding portion or a recessed portion is formed.   The screw terminal structure according to claim 1 or 3, wherein an M3.5 female screw is formed in the screw hole, and an outer diameter of the insulating member is 20 mm. A display device that enables display drive by relaying electric power or an electric signal using the screw terminal structure according to any one of claims 1 to 5.

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