JPH0327710Y2 - - Google Patents

Description

[Detailed Description of the Invention] Purpose of the Invention (Field of Industrial Application) The present invention relates to a mold for a cap fitting for an insulator, which is provided with an engaging recess for engaging an insulator pin fitting and a skirt portion for holding an insulator. It is something.

(Prior Art) In general, most cap metal fittings for insulators are manufactured by casting (mallable or ductile), and only a few are manufactured by forging. The reason for this is that forged insulator cap fittings are basically superior in quality and reliability compared to cast ones, but the structure of the cap fittings, especially the socket part, is not suitable for forging, so machining costs are high. This is because the cap metal fittings are expensive and cannot compete with castable cap metal fittings from an economic point of view.

Conventionally, as a method for manufacturing a cap fitting for a pole socket type suspension insulator, there is a method disclosed in Japanese Patent Publication No. 35-984, and the mold used in this manufacturing method is an upper mold as shown in Fig. 18. 51
and a lower die 52. Then, by using this mold, a bottomed cylindrical engagement wall portion 53 is formed.
a and the skirt portion 53b are pressed from above and below to form the engaging wall portion 53a.
The distal end portion of the engaging wall portion 53a is curved inwardly.
An engaging recess (socket portion 53c) as shown in FIG. 19 was formed inside the socket.

(Problems to be Solved by the Invention) However, since the conventional molding die for the cap metal fitting described above has a structure in which the cylindrical engaging wall portion 53a is simply curved, the engaging wall portion 53a is curved in the subsequent process. It is necessary to cut out one side of the portion 53a by milling to form an opening 53d for introducing the insulator pin fitting into the engagement recess 53c from the side, which improves productivity. Not only is this impossible, but the grain flow lines of the engaging wall portion 53a are cut, resulting in a problem of lowering the strength. In particular, when the engaging recess 53c is forged, it is necessary to cut an undercut part on the inner top surface in a later process, so the grain flow line on the inner top surface, which requires the most strength, is cut, resulting in an emergency. It was a problem.

Focusing on such problems, the applicant of the present invention has already developed a method in which an opening can be formed at the same time as an engaging recess on the inside of the engaging wall when the engaging wall of the cap fitting is curved. We proposed a mold for cap metal fittings.

However, in the mold of this prior application, there was a problem that the mold was divided into a plurality of parts, and the mold release operation of each mold became extremely complicated.

Structure of the device (means for solving the problem) In order to solve the above-mentioned problems, this device is a further improvement to the mold structure of the earlier application, and the skirt of the cap metal fitting is improved. an inner mold that fits on the inner surface of the cap metal fitting; an outer mold that fits on the outer surface of the cap metal fitting; a first engaging recess forming mold having a slanted molding surface that presses from above and below to curve the engaging wall portion inward to form an engaging recess; and a center of the first engaging recess forming mold. and a second engagement recess molding die, which is accommodated in a housing groove cut out from the outside to the outside, and has an opening in the engagement wall and molds an inner wall of the engagement recess. , the second engagement recess mold is connected to an opening mold, an undercut mold that is removably joined to the opening mold in the vertical direction, and a mold that is removably joined to the undercut mold. The opening mold of the second engaging recess mold and the first engaging recess mold are provided with a separation mold of the first engaging recess mold. In order to release the opening mold in the same direction as the mold moves in the direction of the mold, a method is adopted in which engaging means that can be engaged with each other are provided.

(Function) By adopting the above-mentioned means, this invention allows an opening to be formed at the same time as an engaging recess is formed inside the wall by curving the engaging wall of the cap fitting in the manufacturing process of the cap fitting. In addition to improving productivity, the opening mold forms an opening on one side of the engagement wall without cutting, so the grain flow line is not cut, and therefore the engagement recess of the cap metal fitting is not cut. Strength is increased.

Also, an undercut part is formed on the inner top of the engagement recess by an undercut mold during molding, and at this time, the mold is first removed from the separation drawing mold, and then the undercut mold is used to form the opening. By separating the undercut mold from the undercut portion, and then pulling out the undercut mold, the undercut portion can be accurately placed on the inner top surface of the engagement recess without using a milling cutter or the like. This eliminates the need for cutting the openings and undercuts, and eliminates the need to cut grain flow lines, improving strength.

Further, when releasing the first engaging recess mold, the opening mold of the second engaging recess mold is integrally moved in the same direction in conjunction with the releasing movement, and the releasing operation is performed. It becomes extremely easy and productivity increases significantly.

(Example) Hereinafter, an example embodying the present invention will be described based on the drawings.

FIG. 1 shows a stage of the molding process of the cap metal fitting, that is, an engaging wall portion 1 of a cap metal fitting original form 14, which will be described later.
4b is bent to form the engagement recess 14f and the main mold used in the third step of the three steps of forming the opening 14a is shown in an exploded state upside down. In the figure, 1 is an inner mold that fits on the inner top surface of the skirt portion 14c of the cap metal fitting original form 14, and 2 is an outer mold that has a molding surface 2a that fits on the outer peripheral surface of the cap metal fitting original form 14. It is composed of molds 2A and 2B.

Reference numeral 3 denotes a first engaging recess mold which is fitted into a fitting hole 2b continuously formed at the lower part of the molding surface 2a of the outer mold 2 so as to be movable in the vertical direction. As shown in Figure 16, the original cap metal fitting 1
A substantially curved oblique molding surface 3a is formed by pressing the tip of the engagement wall 14b of No. 4 from above and below and curving the engagement wall 14b inward to form the engagement recess 14f. From the center to the outer surface, a housing groove 3b into which a second engagement recess forming mold 4, which will be described below, is fitted is cut out in the vertical direction.

4 is accommodated from the insertion groove 2c on the circumferential side of the outer mold 2 to the accommodation groove 3b of the first engagement recess mold 3,
and an opening 14a on one side of the engagement wall 14b.
It is a second engagement recess forming mold for molding the undercut portion 14g on the inner top surface of the engagement recess 14f, and is divided into three members as shown in FIG. . 5 is an opening mold forming the second engaging recess mold 4,
A curved molding surface 5b is formed at one end edge of the core portion 5a for molding the inner peripheral edge of the distal end of the engaging wall portion 14b into an arc shape.

A stepped engagement convex portion 5c is formed on the outer circumference of the other end of the opening mold 5, and a stepped engagement convex portion 5c is formed in the housing groove 3b of the first engagement recess mold 3. A recess 3c is formed, and the engagement protrusion 5c and the engagement recess 3c constitute a locking means. Then, when the first engaging concave molding die 3 is released upward in FIG.
c and 5c engage with each other, and the opening forming mold 5 is integrally moved upward to be released from the mold.

Reference numeral 6 denotes an undercut mold that is connected to the lower surface of the opening mold 5 so as to be able to be separated downwardly (upside down in FIGS. 1 and 2), and has a longitudinally extending engagement at its base. A matching groove 6a is formed. Further, a disk-shaped core portion 6b corresponding to the molding surface 5b of the opening mold 5 is integrally formed at the tip of the undercut mold 6 to bulge out.
A locking portion 6c is formed on one side edge of b to abut against the side end surface of the opening mold 5 to prevent it from coming off laterally.

7 is the lower surface (first
It is a separate pull-out die that is joined so that it can be pulled out to the side (upside down in the figures and FIG. An engaging pin 7a is provided protrudingly, and a core portion 7b corresponding to the core portion 6b of the undercut mold 6 is provided at the tip end. and,
When the separation drawing die 7 is pulled out by a predetermined amount to the left in FIG. 14, the undercut forming die 6
falls into the recess 7c on the separation pull-out die 7, and is moved downward and away from the undercut portion 14g, and then, due to the engagement between the engagement pin 7a and the left end edge of the engagement groove 6a, the undercut is removed. Cut mold 6
is adapted to be pulled out and moved to the left in conjunction with the separation drawing die 7.

Next, the cap metal fittings 43
A method of forging will be explained with reference to FIGS. 3 to 16.

First, a long round bar is cut into a predetermined length to form a cylindrical material 8 as shown in FIG.

Next, the same material 8 is pressed from above and below by upper and lower forging dies (not shown) to forge a flat material 9 having a protrusion 9a at the center of the lower surface as shown in FIG.

Thereafter, as shown in FIGS. 5 to 7, the material 9 is made by a forging die consisting of an upper die 10, a lower die 11, an opening forming die 12, and a knock pin 13 for extrusion.
are stepped into the cavity shape of the same mold to form an original shape 14 of a cap metal fitting 43, which will be described later. At the time of molding this cap metal fitting original form 14,
The lower end has an opening 14 on one side as shown in Figure 6.
A substantially horseshoe-shaped engagement wall portion 14b having a shape of 1.a is formed, a cylindrical skirt portion 14c is formed at the upper part, and a partition wall 14d is integrally formed at the boundary between the engagement wall portion 14b and the skirt portion 14c. It is formed.

Next, as shown in FIGS. 8 to 10, the original cap metal fitting 14 is forged into its cavity shape using a forging die consisting of an upper die 15, a lower die 16, an opening forming die 17, and a knock pin 18. The height of the engagement wall portion 14b and the height of the skirt portion 14
An annular stepped portion 14e having an L-shaped cross section that bulges outward is formed around the entire circumference of the bottom portion of the partition wall 14d, thereby making the partition wall 14d thin.

Next, as shown in FIG. 11, a lower mold 41 fixed to the mounting member 40 is used, and an upper mold 4 having a bore that abuts at least the outside of the hem of the skirt portion 14c.
2 presses the upper surface S of the annular stepped portion 14e to curve the annular stepped portion 14e inward about its base E. In this way, two upper and lower levels of retaining protrusions 14i are formed on the inner circumferential surface of the hem portion of the skirt portion 14c.

Thereafter, in three steps shown in FIGS. 12, 13, and 15, the forging die according to the invention is used to curve the tip of the engagement wall 14b of the cap metal fitting original 14 inward. , same wall part 14
An engagement recess 14f is formed inside b, and an undercut portion 14g is formed on the inner top surface of the engagement recess 14f.

That is, in the first step shown in FIG. 12, one mold 2A of the inner mold 1 and the outer mold 2 mounted on the upper and lower mounting members 21 and 22, and a pair of similar configurations to the first engaging recess forming mold 3 are used. molds 3X, 3Y,
the opening molding die 5, the undercut molding die 6,
A separate drawing die 7 or the like is used. Then, in a state where the cap metal fitting original form 14 as shown in FIG. 13 is fitted and supported on the inner mold 1, the mold 2A is approached from the outside and is tightened and fixed by the fixed mold 23.
Next, the opening mold 5 is lowered with the undercut mold 6 and the separation drawing mold 7 inserted from the side between the engaging wall portions 14b of the original shape 14, and then the molds 3X and 3Y are sequentially moved. The engaging wall portion 14b is lowered to form an engaging recess 14f and an undercut portion 14g.

After this processing, as the mounting member 22 rises, the fixed mold 23 and the two molding molds 3X and 3Y as the first engaging recess molding molds are moved upward, and from above the engaging wall portion 14b of the cap metal fitting original form 14. Released from the mold. At this time, since the engagement recess 3c is engaged with the engagement protrusion 5c as the mold 3Y rises, the opening mold 5 is also raised integrally, and the engagement wall 14
The mold is released upward from between b. In this state, the cap metal fitting original form 14 is attached to the mounting member 21, the inner mold 1,
The outer mold 2 is moved to the right together with the mold 2A, the undercut forming mold 6, and the separation drawing mold 7, and then the second process shown in FIG. 13 is performed.

In this second step, two molds 3 are used as the first engaging recess molds in the first step.
One mold 3Z is used instead of X and 3Y, and the opening mold 5 is used as an undercut mold while the mold 2A is tightened and fixed from the outside by lowering the fixed mold 23 in the same manner as described above. 6 He descended above;
Thereafter, the forming die 3Z is lowered, and the engaging wall portion 14b of the cap metal fitting original form 14 is shaped so as to approach a predetermined shape. In addition, in this second step, as shown in FIG. 14, as the movable cam body 25 descends, the teardrop mold 24 pulls the cap metal fitting from the side opposite to the undercut mold 6 and the separation drawing mold 7. Engagement wall portion 14 of original form 14
b, and the engaging wall portion 14b
A teardrop 14h is formed on the outer surface of the holder.

After this processing, the mounting member 22
As the cap metal fitting original form 14 is raised, the fixed mold 23 and the forming mold 3Z as the first engaging recess forming mold are raised and released from the engaging wall portion 14b of the cap metal fitting original form 14. or,
In this case as well, as the mold 3Z rises, the engagement recess 3c engages with the engagement protrusion 5c, and the opening mold 5 is moved upward integrally with the mold 3Z. Furthermore, as the mounting member 22 rises, the first
The movable cam body 25 shown in FIG. 4 is also raised, and the teardrop mold 24 is released and moved outward. In this state, the cap metal fitting original 14 is moved to the right together with the mounting member 21, the mold 2A of the inner mold 1 and the outer mold 2, the undercut mold 6, and the separation drawing mold 7, as shown in FIG. Processing in the third step is performed.

In this third step, each mold shown in FIG. 1 and FIG. The part forming die 5 is lowered onto the undercut forming die 6, and then the forming die 2B constituting the outer mold 2 and the first engaging recess forming die 3 are sequentially lowered to form the engaging wall portion of the cap metal original form 14. 1
4b is finished and shaped into a predetermined shape.
Thereby, as shown in FIG.
An engagement recess 14f having an opening 14a on one side is formed inside the engagement recess 4b, and an undercut portion 14g is formed on the inner top surface of the engagement recess.

After this processing, as the mounting member 22 rises, the fixed mold 23, the first engaging recess mold 3, and the mold 2B are raised, and the cap metal fitting original form 14 is raised.
The mold is released from above the engaging wall portion 14b. Also in this case, as the first engaging concave molding die 3 rises, the engaging concave portion 3c engages with the engaging convex portion 5c, and the opening molding die 5 engages with the first engaging concave molding die 3. The mold is moved upward as one unit.

Further, at the end of this third step, the positioning member 26 shown in FIG. 14 is raised as the mounting member 22 is raised, and the outside of the separation drawing die 7 is opened, and in this state, the side of the drawing member 27 is lifted. Due to the horizontal movement, the separation/pulling die 7 is pulled out and moved to the left side in the figure via the engagement pin 27a and the engagement hole 7d.
Then, when the separation drawing die 7 is moved by a predetermined amount,
The undercut molding die 6 falls into the recess 7c on the separating and drawing die 7 and is released downward, and the core portion 6b is separated downward from the undercut portion 14g. Thereafter, the engagement pin 7a engages with the left edge of the engagement groove 6a, and the undercut mold 6 is integrally pulled out to the left side in conjunction with the withdrawal movement of the separation and pull-out mold 7.

After the mold is released, a hole 14j for passing a pin is drilled at the bottom of the tear drop 14h on the engagement wall 14b, as shown in FIG. 16.

The manufacturing of the cap metal fitting 43 is completed through the steps described above. Cap fitting 43 thus obtained
is fitted and fixed, for example, to the head 44a of the suspension insulator 44 with cement 45, as shown in FIG. A pin fitting 46 fixed to the lower part of another suspension insulator 44 is engaged with the engagement recess 14f in the upper part of the cap fitting 43.

Note that the present invention can also be embodied in the following embodiments.

In the embodiment described above, the opening 14a was formed during molding of the engagement wall portion 14b, but in the pre-forging process using the first engagement recess mold 3 and the second engagement portion mold 4, the opening 14a was formed from the beginning. to form. In this case, it is desirable to previously reduce the thickness of the engaging wall portion 14b at the portion where the opening portion 14a is formed.

Effects of the invention As described in detail above, this invention can curve the engaging wall of the cap fitting to form an engaging recess inside the wall and at the same time form an opening. , the opening and undercut portion can be forged with high precision using the second engagement recess molding die without any special processing such as cutting on the engagement wall. The strength of the engaging recess can be improved without cutting the wire at all, and the opening mold of the second engaging recess mold can be integrated with the release movement of the first engaging recess mold. This has the effect of making the mold release movement extremely easy and increasing productivity.

[Brief explanation of the drawing]

Fig. 1 is an exploded perspective view showing one embodiment of the cap metal mold of this invention, Fig. 2 is an enlarged exploded perspective view of only the second engagement recess mold, and Figs. 3 and 4 are the cap metal fittings. Figure 5 is a front view showing the materials for the original shape in the processing order, Figure 5 is a sectional view showing the forging process of the original cap metal fitting, Figure 6 is a bottom view of only the original shape, Figure 7
The figure is a partial sectional view of the original shape, Figure 8 is a sectional view showing the next forging process of the cap metal fitting original shape, Figure 9 is a bottom view of only the same original shape, Figure 10 is a partial sectional view of the same original shape, and Figure 11 is a bottom view of the same original shape. The figure is a sectional view showing the forging process of the retaining protrusion, and Figure 12 shows the first of three forging processes to form an engagement recess and an undercut in the engagement wall of the original cap metal fitting. Cross section, 13th
The figure is a cross-sectional view showing the second step, FIG. 14 is a cross-sectional view taken along line A-A in FIG. 13, FIG. 15 is a cross-sectional view showing the third step, and FIG. 16 is a plan view of only the original shape after processing Figure 17 is a sectional view showing how the cap metal fitting is used, Fig. 18 is a sectional view showing a conventional molding die for the cap metal fitting, and Fig. 19 is a sectional view showing the cap metal fitting molded using the conventional molding die. FIG. DESCRIPTION OF SYMBOLS 1... Inner mold, 2... Outer mold, 3... First engagement recess mold, 3a... Oblique molding surface, 3b... Accommodating groove,
3c...Engagement recess constituting the engagement means, 4...Second engagement recess mold, 5...Opening mold, 5b...
... Molding surface, 5c... Engagement convex portion constituting engagement means, 6... Undercut mold, 6b, 7b...
... Core part, 7 ... Separation pull-out mold, 14 ... Cap metal fitting original form, 14a ... Opening part, 14b ... Engagement wall part, 14c ... Skirt part, 14f ... Engagement recessed part, 14g ... Under Cut portion, 43...cap metal fittings.

Claims (1)

[Scope of Claim for Utility Model Registration] 1. An inner mold that fits on the inner surface of the skirt portion of the cap metal fitting, an outer mold that fits on the outer surface of the cap metal fitting, and an inner mold that fits into the outer mold so as to be movable in the vertical direction. a first engaging recess molded with an oblique molding surface that presses the tip of the engaging wall of the cap fitting from above and below to curve the engaging wall inward to form an engaging recess; a mold; and a housing groove formed in a notch from the center to the outer side of the first engagement recess forming mold, an opening in the engagement wall, and a mold for molding the inner wall of the engagement recess. a second engaging recess mold, the second engaging recess mold being connected to an opening mold, and an undercut mold that is releasably joined to the opening mold in the vertical direction. and a separate pull-out mold releasably joined to the undercut mold, and an opening mold of the second engagement recess mold;
The first engaging recess forming mold is capable of engaging with each other in order to move the opening forming mold in the same direction in relation to the movement of the first engaging recess forming mold in the releasing direction. A mold for a cap metal fitting for an insulator, characterized in that it is provided with an engaging means. 2. The undercut mold of the second engagement recess mold is designed to be released from the mold in the vertical direction and then pulled out laterally as the separation and pull-out mold is pulled out laterally. A mold for a cap fitting for an insulator as set forth in claim 1 of the utility model registration claim. 3. The mold for an insulator cap fitting according to claim 1, wherein the oblique molding surface of the first engagement recess mold is formed into a curved surface. 4. The opening mold forming the second engaging recess mold is provided with a molding surface for molding the inner circumferential edge of the distal end of the engaging wall into an arc shape. A mold for the insulator cap fittings described.