JPS6030258B2 - Molding method for finger plates for telephones - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a finger gaff for a telephone made of synthetic resin.

Regarding the rate forming method. [Prior Art] As is well known, a telephone finger plate has one solid finger hole in its outer annular portion, but these finger holes are uniformly distributed over the entire circumference of the annular portion. Rather, this annular portion is divided into a finger hole-equipped portion and a finger-hole-less portion, and only the finger hole-equipped portion is provided with one solid finger hole.

[Problem that the invention seeks to solve]

When finger plates for telephones with such unevenly distributed finger holes are integrally formed from a synthetic resin material, conventionally one mold has a split structure, and the fingers of the finger plate are separated when the mold is released. At the same time as the mold forming the hole was removed, the finger plate formed from the mold forming the finger plate itself was released from the mold using an extrusion pin.

However, in such a molding method, the finger holes are not uniformly distributed over the entire surface of the finger plate. The mold release conditions were different between the established part and the open hole part. If the mold release conditions are different in this way, the finger plate will be released in an inclined state with respect to the joint surface of the pair of molds used to mold it. The disadvantage is that the recesses and the like, which are commonly used in instruction card games, cause shape defects, which increases the rate of defective products. [Method for Solving the Problems] In order to solve the above problems, the present invention molds a finger plate for a telephone by the following method.

That is, a movable core is relatively movably incorporated into one of a pair of molds in which a cavity for molding a telephone finger plate having non-uniformly distributed finger holes is formed, and a protruding pin is attached to this movable core. When the mold is opened, the finger plate is held by the movable core and the other mold, and the finger plate is inserted into the mold so that it can be slid freely. is carried out,
After the mold is released from the other mold, it is projected from the movable core by the projecting pin.

[Function] Therefore, due to appearance constraints, the protrusion position of the ejector pin has to be placed in the center, and furthermore, when molding a finger plate that has a plurality of finger holes unevenly distributed around the periphery, it is difficult to separate the finger plate. During molding, the finger holes are removed smoothly, preventing shape defects and achieving good molding with high dimensional accuracy.

[Embodiments] The present invention will be explained in detail below using embodiments shown in the drawings.

Figures 1a and 1b schematically show a finger plate for a telephone to which the molding method according to the present invention is applied.To briefly explain this, this finger plate 1 is integrally formed of a synthetic resin material. A flat recessed part 2 for placing an instruction card is formed in the center thereof, and an annular groove 3 for attaching a force bar is formed on the outside thereof, and a finger hole arrangement part 4a of the annular part 4 on the outside thereof is formed. One solid finger hole 5 is formed in a uniform distribution.

Note that an instruction card 6 is placed in the recess 2 commonly used for instruction card battles, and is fixed with a transparent cover 7. Also, 8a
, 8b are a pair of locking pieces integrally provided on the outer circumferential portion 7a of the transparent cover 7, and these locking pieces 8a, 8b are connected to the cover fixing hole 9a raised near the annular groove 3 for attaching the force bar.
, 9b, respectively. 2 to 5 are for explaining the molding method according to the present invention, and in these figures, the molding die 10 includes a fixed side die 11 fixed to a device (not shown), The movable side mold 13 is fixed to a movable mounting plate 12 which is formed in a generally U-shape as a whole. A cavity 14 having the same shape as the finger plate 1 is formed on the surface of the movable mold 13 that is in contact with the fixed mold 11, and a cavity 14 having the same shape as the finger plate 1 is formed inside the cavity 14. A heated and melted synthetic resin material 16 is injected and filled from an injection port 15. In addition, the movable mold 13
A movable core 18 is slidably held in a holding hole 17 raised in the center of the holding hole 17. said cavity 1 through a central hole 19 suitable for
It is coming within 4 days.

The tip of this protrusion 18a is connected to the instruction card mounting recess 2 and the transparent force bar mounting annular groove 3 of the cavity 14 forming the finger plate.
It is formed into a predetermined shape to handle that part. Also,
The end of the movable core 18 is connected to the first extrusion plate 21 at a constant interval through a connecting pin 201, and the movable core 18 and the first extrusion plate 21 move integrally. The first extrusion plate 21 is this and the front mounting plate 1
A compression coil spring 22 interposed between the holder and the holder 2 provides slidability for movement in the right direction in the figure. Note that 23 is a turn pin that sets the initial position of the movable core 18 and the first extrusion plate 21 during molding against the compression coil spring 22, and one end of this return pin 23 is connected to the first extrusion plate 2.
1, and the other end passes through a second extrusion plate 24 and the movable mold 13, which will be described later, and faces the fixed mold 11. Further, a plurality of through holes are formed in the central portion of the movable core 18 in the axial direction, and a projecting pin 25 is inserted into each of these through holes so as to be movable. In this case, one end of the ejecting pin 25 is connected to the molded product when the mold is released.
That is, the instruction card mounting concave portions 2 of the finger plate 1 are equally pressed. (See the two-dot chain line in FIG. 1) The other end of the ejecting pin 25 is fixed to a second extruding plate 24 that is movably disposed between the first extruding plate 21 and the movable core 18. Furthermore, an extrusion bar 26 is fixed to the back surface of the second extrusion plate 24, and is provided through the mounting plate 12 and the first extrusion plate 21. The push rod 26 is controlled by hydraulic pressure or the like and is moved in the left-right direction independently of the mounting plate 12. Next, the formation of the finger plate 1 and the operation of the template will be explained.

During molding, the state shown in Figure 2 is set, and the fixed side mold 1
By injecting and filling the heated and melted synthetic resin material into the cavity 14 from the injection port 15 of the finger plate. - The mold 1 is molded, and after cooling, it is taken out through a three-step mold release operation described below.

That is, in the first step, as shown in FIG.
The mounting plate 12 is moved to the left to separate the movable mold 13 from the fixed mold 11. At this time, the first extrusion plate 2
1 is given sliding properties to the right by a compression coil spring 22, and as the movable mold 13 moves, it extends from the first extrusion plate 21 and the tip of the turn pin 23 moves toward the fixed mold 11 side. The first extrusion plate 21 and the movable core 1 connected to the first extrusion plate 21
8 is moved to the right in the figure relative to the movable mold 13. Therefore, the movable core 18 slides within the holding hole 17, and its protruding portion 18a protrudes from the front surface of the movable metal member 13. Then, fixed side mold 1
1 is in a stationary state, the molded product, that is, the concave part 2 of the finger plate, which is commonly used in instruction card games, maintains a state in which it is held by the protrusion 18a of the movable core 18 and the stationary mold 11. . Therefore, the above-mentioned movement of the movable side mold 13 allows the mold 13 to be properly separated from the finger plate, thereby forming the finger holes 5 as non-uniformly distributed holes, the recess 2 for instruction card placement, etc. can prevent deformation. In this case, the extrusion rod 26, the second extrusion plate 24, and the ejection pin 25 are moving together with the movable die 13 described above. Next, the second step of mold release is performed by moving the movable mold 13 to the left in the figure so as to further distance it from the stationary mold 11, as shown in FIG.

In this way, the movable core 18 that is locked on the right side of the holding hole 17 of the movable mold 13 also moves to the left side integrally with the mold 13, thereby causing the protrusion of the movable core 18 to Finger plate 1 supported at the tip of 18a
is removed from the stationary mold 11 in that state. Next, as the final step of mold release, as shown in FIG. This is done by moving the tip of the ejecting pin 25 to the right via the second extruding plate 24 and causing it to protrude from the movable core 18.

By doing so, the finger plate 1 is released from the movable core 18 by the ejecting pin 25. Therefore, according to the above-described molding method, the movable core 18 that forms the recess 2 for the instruction card layer of the finger plate 1 and the annular groove 3 for attaching the transparent cover is slid against the movable mold 13. When removing the movable mold 13 from the finger holes 5 provided as non-uniformly distributed holes in the finger plate 1 by separating the movable mold 13 from the fixed mold 11 during mold release, the finger plate 1
is handled and held by the movable core 18 and the stationary mold 11, and then the finger plate 1 as a molded product is separated from the movable core 18 by a protruding pin 25 slidably provided on the movable core 18. This makes it possible to prevent the molded product from tilting during demolding.

As a result, the finger holes 5 provided as non-uniformly distributed holes in the finger plate 1, the concave portion for direct mounting of the instruction card, etc. can be molded with high precision without causing shape defects. [Effects of the Invention] As explained above, according to the present invention, a recess commonly used for instruction card games and an annular groove for attaching a transparent force bar are formed in one of the pair of molds constituting the cavity of the finger plate. A movable core is incorporated so as to be relatively movable, and when the mold is released, the finger plate is sandwiched between the movable core and the other mold when the one mold forming the finger hole moves; After that, the finger plate was cut out from the other mold and was made to protrude from the movable core by means of a protruding pin, so that the finger plate could be removed smoothly and reliably, and the finger holes of the first mold could be arranged easily. Since the mold release conditions for the part and the fingerless hole part are almost the same, the finger plate, the finger hole, the concave part for the instruction card, etc. do not have a defective shape, and the finger plate can be molded with good precision. It has the great effect of being able to

[Brief explanation of drawings]

1A and 1B are a plan view and a sectional view taken along the line 1-1 showing the outline of a finger plate for a telephone, FIG.
5 through 5 are diagrams for explaining the mold release operation of the molded product. 1...Finger plate, 2""" recess for instruction card layer, 3...Annular groove for attaching transparent force bar, 4...Annular part, 4a...Finger hole arrangement Part, 5
...Finger hole "10...Forming mold, 11...
...Fixed side mold, 12...Mounting plate, 13...
...Moving side mold, 14...Cavity, 1
7... Holding hole, 18... Movable core, 20...
...Connection pin, 21...First extrusion plate,
22... Compression coil spring, 24... Second extrusion plate, 25... Ejection pin, 26... Extrusion rod. Figure 1 Figure 5 Figure 2 Figure 3 Figure 4

Claims (1)

[Claims] 1. In a method for forming a finger plate for a telephone set having non-uniformly distributed finger holes by injecting and filling a cavity formed by a pair of molds with a molten synthetic resin material, the first A recess for placing an instruction card and an annular groove for attaching a transparent cover are formed in the mold, and a movable core having a protruding pin is incorporated so as to be relatively movable. The opening operation is
The finger plate is held between the movable core and the second mold, and after the mold is released from the second mold, the finger plate is held between the movable core and the movable core by the operation of the protruding pin. A method for forming a finger plate for a telephone, characterized in that the finger plate is made to protrude from the inside.