JP4859781B2 - Terminal, terminal block and method for manufacturing terminal block - Google Patents

Description

  The present invention relates to a terminal, a terminal block, and a method for manufacturing a terminal block used for connecting electrical equipment and the like, and more particularly to a terminal, a terminal block, and a method for manufacturing a terminal block that can be used in an explosive gas atmosphere.

  For example, a terminal block is used for connection between a power supply device and an electronic device that receives power supply from the power supply device, connection between a sensor and an electronic device that receives an electrical signal from the sensor, and the like. The terminal block is electrically connected to the power supply, sensor, etc. via a lead wire, and the round crimp terminal that is crimp-connected to the tip of the lead wire is screwed with the terminal screw of the terminal block. It is configured.

  FIG. 7 is a perspective view of a conventional terminal block. The case 81 is provided with a terminal portion 82, and the terminal portion 82 is provided with terminals 84 of each pole having terminal screws 83. In order to connect the lead wire 86 having the round crimp terminal 85 to the terminal 84, the terminal screw 83 is passed through the round crimp terminal 85 and the terminal screw 83 is screwed into the screw hole 87. In this connection method, it is difficult to reliably connect the lead wire 86 unless the round crimp terminal 85 is provided.

  FIG. 8 is a diagram showing a configuration of a conventional terminal block that can be connected without providing a round crimp terminal on the lead wire. FIG. 8A is an assembly perspective view of the conventional terminal block, and FIG. Is an exploded perspective view thereof. A case 90 formed by injection molding is mounted with a washer 93 assembled with a terminal plate 91 and a terminal screw 92. The terminal plate 91 is attached to the case 90 by press-fitting the press-fit portion 94 into the slit 95 of the case 90. A round crimp terminal 97 which is a wiring connecting portion integrated with the lead wire is inserted into the storage chamber 96. Thereafter, the terminal screw 92 is screwed into the female screw 98 of the terminal plate 91, whereby the round crimp terminal 97 is held between the terminal plate 91 and the washer 93 for electrical connection. In this case, since the square washer 93 is provided, the lead wire can be held by the terminal plate 91 and the washer 93, and the lead wire can be securely connected even when the round crimp terminal 97 is not provided on the lead wire. It can be connected (refer patent document 1).

JP 2001-050882 A

  Since the conventional terminal block is configured as described above, it is possible to connect the lead wire even when the round crimp terminal integrated with the lead wire is not provided, but the terminal plate is attached to the case. There is a need to press fit into the provided slit, and a gap is generated between the case and the terminal plate due to the mounting of the terminal plate, and there is a problem that it is difficult to impart explosion-proof performance to the terminal block.

  This invention was made to solve the above-mentioned problems, and it can be assembled without causing a gap between the case and the terminal plate while securely fixing the lead wire without using a round crimp terminal, It aims at providing the manufacturing method of the terminal block which improved explosion-proof performance, and a terminal block.

  The terminal according to the present invention includes a connection portion connected to an external device configured inside the terminal block, a terminal element having a screw hole screwed into a terminal screw provided outside the terminal block, and an outer peripheral portion of the screw hole And a rectangular terminal board fitted to the board.

  The terminal block according to the present invention includes a terminal element having a screw hole, a terminal formed by a square terminal plate fitted to the terminal element, a terminal screw screwed into the screw hole of the terminal, and the terminal. A square washer disposed between the terminal screw and locking a lead wire extending from an external device; and a housing portion for placing the terminal, the terminal screw and the square washer, and the housing portion includes a positioning member. And having each of the square shaped terminal plates contact the positioning member to place the terminals in the housing, and fixing the terminals by insert molding.

  The manufacturing method of the terminal block according to the present invention includes: an upper mold that forms an opening side surface of the terminal block; and a lower mold that forms a terminal formation side surface of the terminal block and has a positioning member. In the manufacturing method of the terminal block having the terminal formed by the terminal element having and the rectangular terminal plate fitted to the terminal element, the rectangular terminal plate is fixed in contact with the positioning member, A terminal placement step of placing a terminal in the cavity of the lower mold; a mold placement step of inserting the upper mold into the lower mold and contacting the terminal; and the lower mold A molding step of injecting resin into a cavity between mating surfaces of the mold and the upper mold and insert molding; and a step of taking out the insert-molded terminal block from the upper mold and the lower mold Also It is.

  According to this invention, since the terminal is formed by the terminal element and the terminal plate formed in a square shape, the lead wire can be securely held by the terminal plate formed in the square shape and the square washer. Thus, the lead wire can be securely fixed without using a round crimp terminal. Moreover, since a terminal is comprised with two members, a terminal element and a terminal board, while being able to simplify the manufacturing process of a terminal, manufacturing cost can be suppressed.

  In addition, according to the present invention, the rectangular terminal plate is placed in contact with the positioning member provided in the storage portion of the terminal block, the terminal is arranged, and the terminal is fixed by insert molding. Can be arranged on the terminal block in a certain direction. In addition, since the terminal is fixed by insert molding, there is no gap between the case and the terminal, and the explosion-proof performance can be improved.

  Furthermore, according to the present invention, the lower mold has a positioning member that abuts and fixes the rectangular terminal plate, abuts the rectangular terminal plate against the positioning member, and fixes the terminal to the lower side. Since the terminal arranging step is provided in the cavity of the mold, it is possible to insert-mold by defining the arrangement direction of the terminal plate having a square shape.

Embodiment 1 FIG.
1A and 1B are diagrams showing a configuration of a terminal according to Embodiment 1 of the present invention. FIG. 1A is a perspective view thereof, and FIG. 1B is an exploded perspective view thereof.
The terminal 1 includes a terminal element 2 and a terminal plate 3. The terminal element 2 and the terminal plate 3 are formed of a metal member that is not easily rusted and can be electrically connected, such as brass. The terminal element 2 has a connection part 2a, a body part 2b, a cushion part 2c, an insertion part 2d, and a screw hole 2e shown in FIG.

  The connection part 2a is formed in a shape that can be connected to a terminal such as a switch that is connected to be energized. A knurling that is a linear groove in the axial direction is cut in the body portion 2b to prevent the terminal 1 from being pulled out when the terminal 1 is insert-molded into the terminal block. The cushion part 2c is a groove provided in the circumferential direction on the connection part 2a side upper part of the body part 2b, and absorbs pressure applied from the mold when the terminal 1 is insert-molded into the terminal block. The insertion portion 2d is formed with a smaller diameter than the body portion 2b, and is fitted into an insertion hole 3a formed in the terminal plate 3 described later. The screw hole 2e is an opening provided inside the insertion portion 2d. A screw groove is formed inside the screw hole 2e, and the terminal screw 12 shown in FIG. On the other hand, the terminal plate 3 is formed by punching a metal plate by press working, and the insertion hole 3a is also formed in the same manner. As described above, the insertion portion 2d of the terminal element 2 is inserted into the insertion hole 3a. FIG. 1 also shows a square washer 11 and a terminal screw 12 that are assembled to the terminal 1.

  FIG. 2 is a cross-sectional view showing the terminal assembly according to Embodiment 1 of the present invention. The insertion hole 3a of the terminal plate 3 has a tapered inclined portion 3b on the inner peripheral surface. By inserting and crimping the insertion portion 2d of the terminal element 2 into the insertion hole 3a having the inclined portion 3b, the insertion portion 2d is spread and fixed in a C shape along the tapered inclined portion 3b. The end portion of the insertion portion 2d widened in a letter C is formed so as not to protrude from the outer surface of the terminal plate 3, and is configured not to be caught when a lead wire is disposed on the terminal 1. The fixing of the terminal element 2 and the terminal plate 3 is not limited to the above-described caulking, and heat caulking, press-fitting, or the like may be used as long as electrical conduction is achieved and strength against insert molding can be maintained. Further, as shown in FIG. 2, screw grooves are formed in the screw holes 2e provided inside the insertion portion 2d, that is, inside the body portion 2b.

FIG. 3 is a perspective view showing the configuration of the terminal block in which the terminals according to Embodiment 1 of the present invention are arranged. FIG. 4 is a view of the terminal block in FIG. 3 as viewed from the A direction. The terminal block according to the first embodiment will be described as a terminal block that constitutes a limit switch.
The terminal block 4 has a terminal forming part 5 in which the terminals 1 are arranged in parallel, and an opening part 6 for assembling a micro switch (not shown). The terminal forming part 5 is composed of an upper terminal forming part 7 and a lower terminal forming part 8, and insulating walls 9a and 9b are formed at regular intervals in a direction orthogonal to the upper terminal forming part 7 and the lower terminal forming part 8. Yes. As a result, the upper terminal forming portion 7 and the lower terminal forming portion 8 are partitioned and formed with a plurality of storage portions 10 in a row at regular intervals. A fixed interval is provided between the insulating wall 9a and the insulating wall 9b, and this interval is formed to ensure a longer creepage distance, which is a distance along the surface of the insulator between the two conductive portions. is doing. Also, as shown in FIG. 4, the upper terminal forming portion 7 is provided so as to protrude to the front surface from the lower terminal forming portion 8, and this constitutes a limit switch for two-point detection in the first embodiment. This is because two micro switches are arranged inside the opening 6.

  In FIG. 4, as indicated by dotted lines, the terminals 1 are fixed by insert molding in each of the plurality of storage portions 10 formed. The end of the insertion portion 2 d of the terminal element 2, the screw hole 2 e and the outer surface of the terminal plate 3 are fixed so as to be exposed to the outside of the storage portion 10. A terminal screw 12 is screwed into the screw hole 2 e exposed to the outside via a square washer 11. FIG. 3 shows the structure of the insert-molded terminal 1 without attaching the square washer 11 and the terminal screw 12 to the lower terminal forming portion 8.

  Next, details of the square washer 11 and the terminal screw 12 will be described. As shown in FIGS. 1 and 4, the four corners of the square washer 11 are formed to bend toward the terminal plate 3 side of the terminal 1. When a lead wire is attached to the terminal block 4, a lead wire (not shown) is interposed between the terminal plate 3 of the terminal 1 and the square washer 11, and the terminal screw 12 is fastened and fixed. The lead wire easily moves and comes off when tightened. Therefore, by bending the four corners of the square washer 11 toward the terminal plate 3, the tip of the bending portion is brought into contact with the terminal plate 3, and the lead wire that moves by tightening the terminal screw 12 is locked. This prevents the terminal plate 3 and the square washer 11 from coming off.

Next, a method for manufacturing the terminal block 4 will be described. FIG. 5 is a perspective view showing a mold of the terminal block according to Embodiment 1 of the present invention. FIG. 5 (a) shows the terminal forming part side mold and the opening part side mold, and FIG. ) Is an enlarged view of a part of the terminal forming part side mold. FIG. 5B shows the structure of the mold corresponding to the terminal forming portion 5, and further shows a state in which the terminal 1 is arranged in the terminal forming portion mold.
The terminal block 4 includes a terminal forming part side mold (lower mold) 13 that forms the terminal forming part 5 of the terminal block 4 and an opening part side mold (upper mold) that forms the opening 6 of the terminal block 4. After the terminal 1 is disposed in the cavity of the terminal forming part side mold 13, the opening side mold 14 is pressed against the terminal forming part side mold 13 and the terminal element 2 connection part 2 a of the terminal 1. The resin is injected into the cavity between the mating surfaces of the terminal forming part side mold 13 and the opening part side mold 14 and molded by insert molding.

  As shown in FIG. 5, the terminal forming part side mold 13 includes insulating members 9 a and 9 b and a wall member 13 a that forms the storage part 10, a positioning member 13 b that defines the position of the terminal 1, and the terminal forming part 5. It is comprised by the outer peripheral surface formation member 13c etc. which form the outer peripheral surface of this. The wall member 13a is a protrusion extending in the vertical direction, and by inserting resin and insert molding, the storage portion 10 is partitioned to form the insulating walls 9a and 9b, and the insulating wall 9a and the insulating wall 9b. Create a space between them to ensure the creepage distance.

  The positioning member 13 b is a rectangular protrusion provided at a position corresponding to the upper portion of each storage portion 10 of the terminal block 4. When the terminal 1 is disposed in the cavity of the terminal forming part side mold 13, it is inserted using a jig or the like while contacting one side of the terminal plate 3 formed in a substantially square shape of the terminal 1 to the positioning member 13b. To do. As a result, the terminal plates 3 can be arranged in parallel with each other and in parallel with the one side of the terminal plate 3 and the wall member 13a, and the terminal plate 3 can be insert-molded in the same direction. . The positioning member 13b provided on the terminal forming portion side mold 13 corresponds to the concave portion (positioning member) 10a of the terminal block 4 shown in FIG. 3, and convex portions (positioning members) 10b are formed on both sides of the concave portion 10a. Is done.

  As described above, after the terminal plate 3 of the terminal 1 is arranged in the specified direction in the cavity of the terminal forming part side mold 13, the terminal forming part side mold 13 and the terminal 1 of the terminal 1 of the terminal 1 are provided. The opening side mold 14 is pressed and fixed to the connecting part 2a, and resin is injected into the cavity between the mating surfaces of the terminal forming part side mold 13 and the opening side mold 14 to perform insert molding. When the opening side mold 14 is pressed against the connecting portion 2a, pressure is applied to the terminal element 2. This pressure is absorbed by the cushion portion 2c provided in the terminal element 2, and the screw hole 2e of the terminal element 2 is absorbed. Prevents internal screw grooves from being crushed. Further, the terminal element 2 and the terminal plate 3 which are only caulked and fixed are covered with resin by insert molding and fixed more firmly.

FIG. 6 is a perspective view showing the configuration of the opening of the terminal block according to Embodiment 1 of the present invention.
The terminal block 4 is attached with a plunger 15a, a return spring 15b, an E-ring 15c, and a bolt 15d. This is a one-way assembly structure in which the elastic member 15h, the lid 15i, and the tapping screw 15j for fixing these members are inserted. Inside the opening 6, the connection portion 2 a of the terminal element 2 of the terminal 1 insert-molded on the terminal block 4 is exposed. The connection part 2a of the terminal 1 formed in the upper terminal formation part 7 and the connection part 2a of the terminal 1 formed in the lower terminal formation part 8 are divided into two stages and exposed. Thereby, the microswitch 15e having a short terminal is electrically connected to the connecting portion 2a of the terminal 1 formed in the upper terminal forming portion 7, and the microswitch 15g having a long terminal is formed in the lower terminal forming portion 8. It is electrically connected to the connecting portion 2a of the terminal 1. In the terminal block according to the first embodiment, the two-point detection circuit has been described. However, the single-point detection circuit may be configured, and the present invention is not limited to this.

  As mentioned above, according to this Embodiment 1, since it comprised so that a terminal might be formed with two members, a terminal element and a terminal board, while being able to simplify the manufacturing process of a terminal, it suppresses manufacturing cost. Can do.

  Further, according to the first embodiment, since the terminal plate of the terminal has a substantially square corner shape, and the lead wire is interposed between the corner shaped terminal plate and the square washer with the four corners curved, By tightening the terminal screw, the lead wire does not come off from the terminal plate and the square washer.

  Furthermore, according to the first embodiment, since the positioning member that restricts the arrangement direction of the terminal plate is formed on the terminal forming part side mold, and the terminal plate is brought into contact with the positioning member, the rectangular shape is formed. It is possible to insert-mold with the terminal plates aligned in a certain direction.

  Furthermore, according to this Embodiment 1, since it comprised so that a terminal might be insert-molded, a clearance gap does not arise between a terminal block and a terminal, and explosion-proof performance can be improved.

  In addition, in Embodiment 1 mentioned above, although the structure which provides a rectangular convex part as a positioning member provided in a metal mold | die was shown, even if it provides multiple pins and pinches the upper side and lower side of a terminal board of a terminal Good. Thus, the positioning member is not particularly limited as long as the positioning member can be sandwiched so that the terminal plates of the terminals are arranged in a specified direction.

It is a perspective view which shows the structure of the terminal which concerns on Embodiment 1 of this invention. It is sectional drawing which shows the assembly | attachment of the structure of the terminal which concerns on Embodiment 1 of this invention. It is a perspective view which shows the structure of the terminal block which has arrange | positioned the terminal which concerns on Embodiment 1 of this invention. It is the figure which looked at FIG. 3 from the arrow A direction. It is a perspective view which shows the metal mold | die of the terminal block which concerns on Embodiment 1 of this invention. It is a perspective view which shows the structure of the opening part of the terminal block which concerns on Embodiment 1 of this invention. It is a perspective view which shows the structure of the conventional terminal block. It is a perspective view which shows the structure of the conventional terminal block.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Terminal 2 Terminal element 2a Connection part 2b Body part 2c Cushion part 2d Insertion part 2e Screw hole 3 Terminal board 3a Insertion hole 3b Inclination part 4 Terminal block 5 Terminal formation part 6 Opening part 7 Upper terminal formation part 8 Lower terminal formation part 9a 9b Insulating wall 10 Housing 10a Recess 10b Protrusion 11 Square washer 12 Terminal screw 13 Terminal forming part side mold 13a Wall member 13b Positioning member 13c Outer peripheral surface forming member 14 Opening side mold 15a Plunger 15b Return spring 15c E- Ring 15d Bolts 15e, 15g Micro switch 15f Insulating member 15h Elastic member 15i Lid 15j Tapping screw 81 Case 82 Terminal portion 83 Terminal screw 84 Terminal 85 Round crimp terminal 86 Lead wire 87 Screw hole 90 Case 91 Terminal plate 92 Terminal screw 93 Washer 94 Press-fit portion 95 Slit 96 Storage chamber 97 Round crimp terminal 98 Female Di

Claims (3)

In the terminal fixed to the terminal block by insert molding,
The terminal is connected to an external device configured inside the terminal block, a terminal element having a screw hole screwed into a terminal screw provided outside the terminal block,
A terminal having a rectangular terminal plate fitted to the outer peripheral portion of the screw hole. A terminal element formed of a terminal element having a screw hole and a rectangular terminal plate fitted to the terminal element;
A terminal screw screwed into the screw hole of the terminal;
A square washer disposed between the terminal and the terminal screw and locking a lead wire extending from an external device;
A storage section for arranging the terminal, terminal screw and square washer;
The storage part has a positioning member, the terminal is placed in the storage part by contacting each rectangular terminal plate with the positioning member, and the terminal is fixed by insert molding. Terminal block. A terminal element having a screw hole is fitted to the terminal element by an upper mold that forms the side surface of the opening of the terminal block, and a lower mold that forms the terminal forming part side surface of the terminal block and has a positioning member. In the method of manufacturing a terminal block having the terminal formed of a rectangular terminal plate,
A terminal disposing step of abutting and fixing the rectangular terminal plate to the positioning member, and disposing the terminal in a cavity of the lower mold; and
A mold placement step of inserting the upper mold into the lower mold and contacting the terminal;
A molding step of injecting resin into a cavity between the mating surfaces of the lower mold and the upper mold, and insert molding;
A method for producing a terminal block, comprising: taking out the insert-molded terminal block from the upper mold and the lower mold.

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