JP3906421B2 - Manufacturing method of synthetic resin molded products - Google Patents

Description

[0001]
[Technical field to which the invention belongs]
The present invention relates to a technology for integrally manufacturing a push key button of a telephone set, an operation key button of a keyboard of a personal computer, a push key button of a calculator, and the like, and when inserting these key buttons into a mating part such as a casing. It relates to improvement of insertability or embeddability.
[0002]
[Prior art]
When assembling a telephone, a keyboard of a personal computer, a push key button of a calculator, or the like on a casing or a partner part, each key button is assembled in a predetermined position one by one. This takes time to complete one and the productivity is not good.
[0003]
Further, in order to make the key button movable, a hinge or a spring is required, but the hinge or spring part and the key button are integrally formed of a resin having elasticity or flexibility such as rubber or elastomer.
[0004]
However, since these are opaque or translucent, the design of numbers, letters, etc. must be printed on the surface of the key button, and there are defects such as wear of this design and loss of permanentity due to numerous key button operations. .
[0005]
In order to obtain transparency, the hinge part is made of the above rubber or the like, and the button part may be molded in two colors with a transparent synthetic resin. In this case, if printing is performed on the surface of the rubber, permanent printing can be obtained, but expensive equipment And the process is doubled, resulting in high costs.
[0006]
[Problems to be solved by the invention]
As described above, if a plurality or all of the required number of push key buttons such as telephones can be assembled to the housing or the other part at once, the time for completing one unit is greatly reduced. Productivity is also significantly improved.
[0007]
In addition, the key button is transparent and has a hardness, and the hinge part or the spring part is required to have contradictory functions such as elasticity or flexibility, but it is also necessary to meet this.
[0008]
[Means for Solving the Problems]
The inventors of the present invention have reached the present invention as a result of intensive studies to solve the above problems.
[0009]
In other words, a combination of multiple key buttons that can be moved up and down independently, with a design on the bottom of the key buttons, and each key button connected to the outer frame with a synthetic resin sheet that can be punched By using a plurality of holes previously drilled in the synthetic resin sheet in the resin molded article, and producing a synthetic resin molded article formed by injection molding a molten synthetic resin from the back surface to the surface of the synthetic resin sheet And succeeded in solving the above-mentioned problems. Since the synthetic resin sheet can be punched, it has elasticity and functions as a spring or a hinge. If a transparent material is used for the synthetic resin, printing is performed on the synthetic resin sheet, and the resin key button is placed thereon, so that printing durability can be obtained.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the synthetic resin molded product and the manufacturing method thereof according to the present invention will be described.
[0011]
Multiple key buttons that can be moved up and down independently are integrated, and there are designs (pictures, letters, etc.) on the bottom of the key buttons, and each key button is connected to the outer frame with a synthetic resin sheet that can be punched out. Provided synthetic resin molded products.
[0012]
Multiple key buttons that can be moved up and down independently. Designed on the bottom of the key buttons. Each key button is not connected to the outer frame. The synthetic resin molded product connected with a punchable synthetic resin sheet is provided.
[0013]
A plurality of key buttons that can be moved up and down independently are integrated, and there is a design on the bottom of the key buttons, each key button is connected to the outer peripheral frame with a synthetic resin sheet that can be punched, and some or Provided is a synthetic resin molded product in which all the key buttons are connected to each other at one or more places by the punchable synthetic resin sheet.
[0014]
Multiple key buttons that can move up and down independently are integrated, and there is a design on the bottom of the key buttons, each key button is connected to the outer frame with a synthetic resin sheet that can be punched, or connected to the outer frame Each key button is connected to each other with a synthetic resin sheet that can be punched at one or more locations, or each key button is connected to the outer frame with a synthetic resin sheet that can be punched, and In a synthetic resin molded product in which the key buttons or all the key buttons are connected to each other by the punchable synthetic resin sheet at one or more locations, the thickness of the ink film layer of the printing part is 4 μm or more in a single layer Provided is a backlit synthetic resin molded article having a thickness of not less than 2 μm and not less than 8 μm , wherein the punchable synthetic resin sheet has a thickness of not less than 0.2 mm and not more than 1.0 mm.
[0015]
Each button usually has a pattern such as a pattern, letters, numbers, etc., but in each of the above embodiments, the key button is a colorless and transparent one that does not have a design, or a single color print that does not have a pattern. A synthetic resin molded product is provided.
[0016]
Synthetic resin molded product with multiple key buttons that can be moved up and down independently, with a design on the bottom of the key buttons, and a synthetic resin sheet that can be punched into each key button. A synthetic resin molding manufacturing method is provided, in which a plurality of holes previously opened in the synthetic resin sheet are used, and a molten synthetic resin is injection-molded from the back surface to the surface of the synthetic resin sheet.
[0017]
The punched synthetic resin sheet such as polycarbonate needs to have a thickness of 0.2 mm or more and 1.0 mm or less. If it is thinner than 0.2 mm, the connecting part loses the weight of the button, and it becomes difficult to handle it as a whole as a whole, and it takes a long time to assemble it into the case, improving the ease of installation and greatly increasing the productivity. I cannot expect any improvement. Also, the function as a spring is low.
[0018]
When the thickness of the synthetic resin sheet exceeds 1 mm, a connecting portion that joins the outer peripheral frame and the key button is formed to have a width of about 2 mm so that the key button can move up and down. However, the formation becomes difficult.
[0019]
That is, it is very difficult to punch the synthetic resin sheet so that the thickness of the synthetic resin sheet is 1 mm or more and the width of the connecting portion is 2 mm, for example.
[0020]
Further, when viewed as a spring or a hinge, a large force is required to press the key button. To the key buttons and backlighting possible is the thickness of the ink film to be used in a single layer is 4μm or more, the thickness of the ink film used is required to be 8μm or more, respectively 4μm in two or more layers If it is less than 8 μm , a pinhole is generated and backlighting becomes difficult.

[0021]
Example 1
The synthetic resin sheet 5 made of a polycarbonate sheet having a thickness of 0.5 mm was printed with black ink on the design 6 consisting of numbers from 0 to 9 and two letters, and white printing was performed as a background color from above. The number is 8mm long and 2.5mm wide, and the distance between the numbers is 30mm in the horizontal direction. Three numbers are arranged in the horizontal direction, and four numbers and two types of letters are arranged in the vertical direction. The vertical spacing between letters and numbers was 30 mm. The above 12 numbers and letters are made into one set, and this is printed on a polycarbonate sheet having a width of 75 mm and a length of 105 mm (FIG. 2), but the size of the original polycarbonate sheet is 380 mm × 530 mm. 25 sets of letters and numbers are printed. This polycarbonate sheet is punched into one set (FIG. 2). At the same time, a total of 12 holes with a diameter of 4 mm are formed at positions 12 mm away from the center of letters and numbers in the upper left direction.
[0022]
The printed surface of the polycarbonate sheet punched into each set is inserted into a fixed mold of an injection mold (inserted and fixed using an injection mold mounting hole 8 as shown in FIG. 2), and the mold is closed. Using a 4 mmφ injection molding gate hole 7 as a back gate, a molten polycarbonate resin is injected from the opposite side of the printed surface of the polycarbonate sheet toward the printed surface, the mold is opened after cooling, and the polycarbonate sheet and the polycarbonate resin A synthetic resin molded product with welded was obtained. The injected polycarbonate resin portion had a circular key button having a thickness of 4 mm and a diameter of 16 mm on a base having a thickness of 1 mm and a length and width of 16 mm.
This synthetic resin molded product is punched into the outer peripheral frame 1 (FIG. 1) having a width of 2 mm and the polycarbonate resin portion using a punching die. The polycarbonate resin portion and the outer peripheral frame 1 forming the key button 3 (FIG. 1) Some key buttons 3 (designated number 5 and 8 key buttons in FIG. 1) are other key buttons so that one or two connecting portions 2 (FIG. 1) having a width of 2 mm remain between them. And punched so as to be connected by one or two connecting portions having a width of 2 mm.
[0023]
The synthetic resin molded product thus manufactured is one in which the key buttons 3 of numbers and letters are independently operated up and down, and twelve key buttons 3 are connected as a whole and handled as one or one set. I was able to build it in 2 seconds.
[0024]
On the other hand, it took 10.5 seconds when twelve key buttons 3 were disassembled and assembled one by one into the housing as in the conventional product.
[0025]
(Example 2)
In Example 1, numbers, letters and background colors to be printed on the polycarbonate sheet were printed by the screen printing method.
[0026]
Further, the ink layer from which numbers and characters were removed as the background color was printed in black, and this was repeated twice to print the ink film layer with a thickness of 15 μm .
[0027]
Further, letters and numbers were printed with red ink, and the ink film layer was 7 μm .
[0028]
The printed polycarbonate sheet was processed in the same manner as in Example 1, and the manufactured synthetic resin molded product was assembled in a housing and backlit. Red numbers and letters emerged, giving it a beautiful appearance.
[0029]
(Example 3)
In Example 1, four sets of twelve key buttons are provided, and four sets of cavities are provided in the mold so that four sets of synthetic resin molded products are obtained. Got. These were installed in the case, but the time was 2.2 seconds.
[0030]
【The invention's effect】
(1) Improvement of productivity (1) One set of key buttons incorporated into a telephone or the like can be made at a time.
(2) A set of key buttons can be assembled in a short time into the housing, greatly improving productivity.
[0031]
(2) Cost reduction As described in (1) above, the improvement in productivity leads to a significant reduction in manufacturing and assembly costs. Further, since the spring or hinge part and the key button part can be produced at a time, the cost can be greatly reduced.
[0032]
(3) Appearance of Appearance Printed back of key buttons having a pattern with a film thickness of a predetermined thickness or more exhibited a beautiful appearance without light leakage.
[Brief description of the drawings]
FIG. 1 is a perspective view of a synthetic resin molded product according to the present invention.
FIG. 2 is a surface view of a synthetic resin sheet printed with holes according to the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Outer periphery frame 5 ... Synthetic resin sheet 2 ... Connection part 6 ... Design 3 ... Key button 7 ... Hole for injection molding gate (12 pieces)
4 ... Design 8 ... Injection mold mounting hole

Claims (1)

A design by printing is applied to the corresponding portion of the synthetic resin sheet corresponding to the bottom surface of the plurality of key buttons, a plurality of holes are opened in the synthetic resin sheet,
A plurality of key buttons are integrally arranged on the synthetic resin sheet by injection molding a molten synthetic resin from the back surface to the front surface of the synthetic resin sheet using the plurality of holes,
The synthetic resin sheet is punched with a punching die, and an outer peripheral frame of the synthetic resin sheet and a connecting portion for connecting the outer peripheral frame and a part of the plurality of key buttons are provided, and adjacent key buttons are By providing a connecting part that connects at one place or more,
A plurality of key buttons that can be moved up and down independently are integrally arranged on a synthetic resin sheet, and a design is applied to a corresponding portion of the synthetic resin sheet corresponding to the bottom surface of the plurality of key buttons.
A method for producing a synthetic resin molded product.

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