JPH07138783A - Mark forming method for metal mold - Google Patents

Abstract

PURPOSE:To form marks without degrading the dimensional accuracy of a metal mold regardless of renewing of marks by putting an electrolyte into a storage tank frame placed on a masking tape stuck to the molding surface of the metal mold and energizing the electrolyte. CONSTITUTION:The masking tape 11 blanked with the marks necessary for management, such as figures, symbols and characters, is stuck onto a chrome plating layer C which is the molding surface 10' of the metal mold 10 at the time of forming the marks to be transferred to glass articles on the metal mold simultaneously with molding of the glass articles. The electrolyte 13 storage tank frame 12 is so installed thereon as to enclose the mark forming part. The electrolyte 13 is injected therein. An anode rod 14 is immersed into the electrolyte 13 and is energized by forming a circuit consisting of the metal mold 10 as a cathode. The desired marks are formed on the chrome plating layer C of the molding surface 10' at the point not coated with the masking tape 11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming marks on a mold, and more particularly to a method for forming marks on a mold which are transferred to a glass article at the same time when the glass article is molded.

[0002]

2. Description of the Related Art For example, glass articles for cathode ray tubes such as panels or funnels produced by glass makers are then sent to tube makers and finally finished as cathode ray tubes through a manufacturing process there. However, during the manufacturing process of the tube maker, or even after it is completed as a cathode ray tube, defects such as cracks and breaks may occur in the panel and funnel. It is necessary to retrospectively investigate the manufacturing period of glass. Also, in production control and inventory control, it is necessary to know promptly and surely the items required for control for each glass article.

Therefore, conventionally, marks such as numbers, symbols, or letters are formed on a glass article in a molding die, and the marks are transferred onto the surface of the glass article at the same time when the glass article is molded, so that individual marks can be formed. We manage glass articles.

By the way, usually, the molding surface of the mold is coated with chrome plating for the purpose of releasing from the glass.
As a conventional method for forming a mark on a mold, as shown in FIG. 3, a mark is directly formed on a molding surface 10 'of the mold 10 by an etching or engraving machine, and a chrome plating layer is formed on the mark by plating. C is formed, or, as shown in FIG. 4, a chrome plating layer C is formed on the molding surface 10 ′ of the mold 10, and then marks are formed by sandblasting.

[0005]

However, in the above-mentioned conventional mark forming method, since the mark is engraved on the molding surface of the mold itself, when the mark is renewed, the molding surface of the previous mark forming portion is formed. Is ground again and new marks are formed on it, so that by repeating this, there arises a problem that the dimensional accuracy of the mold is gradually deteriorated. In particular, for temporary marks such as the date of manufacture, since the marks are frequently updated, if the dimensional accuracy deteriorates due to grinding of the mold, it is possible to stabilize glass articles for cathode ray tubes that require high molding accuracy. Since the molding cannot be performed and the repair work for recovering the dimensional accuracy of the mold must be frequently performed, there arises a problem that the labor and cost for the work are required.

Therefore, an object of the present invention is to provide a mark forming method for a die which can form the mark regardless of the renewal of the mark without deteriorating the dimensional accuracy of the die.

[0007]

The present invention has been made in view of the above problems and objects, and a masking tape is attached to a molding surface of a mold and an electrolytic solution storage tank frame is installed on the masking tape. This is a method for forming a mark on a die, which is characterized in that a plating layer is deposited on a portion which is not covered with the masking tape by energizing the electrolytic solution injected into the storage tank frame.

[0008]

According to the mark forming method of the present invention, by energizing the electrolytic solution in the electrolytic solution storage frame installed on the molding surface to deposit the plating layer on the portion not covered with the masking tape, A desired mark is formed on the molding surface of the mold.

[0009]

EXAMPLES The method of forming marks on the mold according to the present invention will be described below with reference to examples.

FIG. 1 is an enlarged sectional view for explaining the mark forming method of this embodiment, and FIG. 2 is an enlarged perspective view of a molding surface of a die on which marks are formed.

10 is a mold, 11 is a masking tape, 1
Reference numeral 2 is an electrolytic solution storage tank frame, 13 is an electrolytic solution, and 14 is an anode rod. A chrome plating layer C having a thickness of 15 to 40 μm is formed on the molding surface 10 ′ of the mold 10 for releasability from glass.

First, a masking tape 11 is formed by cutting out marks required for management of numbers, symbols or characters on a molding surface 10 'of a die 10 for forming marks, which is a chrome plating layer C in this embodiment. An electrolyte solution storage tank frame 12 is installed on the masking tape 11 so as to surround the mark forming portion while being attached.
The electrolytic solution 13 is injected into the inside. When the electrolytic solution storage tank frame 12 is installed, the adhesive tape 15 is interposed on the contact surface between the electrolytic solution storage tank frame 12 and the chrome plating layer C of the molding surface 10 'to ensure that the electrolytic solution 13 does not leak. Seal on. As the electrolytic solution 13, nickel chloride (200 g /
1) and a plating solution containing hydrochloric acid (100 ml / l) as a main component is used. Then, the anode rod 14 is dipped in the electrolytic solution 13 to form a direct current circuit using the mold 10 as a cathode,
A current is applied at 1.5 to 2.5 V and 0.3 to 1.0 A for 10 to 15 minutes, and a nickel plating layer N is formed on the chrome plating layer C on the molding surface 10 ′ which is not covered with the masking tape 11. To form. As a result, the molding surface 10 ′ of the mold 10
A desired mark is formed on the chrome-plated layer C.

In the case of renewing the mark, it is sufficient to grind the plating layer forming the mark of the mold and then form the mark again in the above-mentioned manner, and it is not necessary to grind the molding surface of the mold itself. Therefore, the marks can be formed on the mold without deteriorating the dimensional accuracy of the mold.

[0014]

As described above, according to the mark forming method for a mold of the present invention, even if the mark is frequently formed on the mold by renewing the mark, the dimensional accuracy of the mold is not deteriorated. Mark formation can be performed favorably.

[Brief description of drawings]

FIG. 1 is an enlarged cross-sectional view for explaining a method of forming a mark on a mold according to the present invention.

FIG. 2 is an enlarged perspective view of a molding surface of a mold on which marks are formed.

FIG. 3 is an explanatory diagram of a conventional mark forming method of a mold.

FIG. 4 is an explanatory diagram of a conventional mark forming method of a mold.

[Explanation of symbols]

 10 Mold 11 Masking Tape 12 Electrolyte Storage Tank Frame 13 Electrolyte 14 Anode Rod 15 Adhesive Tape C Chromium Plating Layer N Nickel Plating Layer

Claims (1)

[Claims] 1. A portion which is not covered with a masking tape by attaching a masking tape to a molding surface of a mold, installing an electrolyte solution storage tank frame thereon, and energizing the electrolyte solution injected into the storage tank frame. A method for forming a mark on a die, which comprises depositing a plating layer on the spot.