JPS5834415B2 - Glass Oshigata Seikeiyou Kanagata no Hoseihouhou - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for correcting a mold for press molding glass, particularly a method for correcting a mold for a cathode ray tube panel.

Bushiun tubes generally require strict dimensional accuracy,
In particular, strict precision is required for the inner radius of the panel.

The inner surface radius of this panel is largely determined by the quality of the surface radius of the plunger, which is the mold for forming the panel.

In general, plungers are manufactured to design target values taking into account shrinkage and deformation during glass solidification. However, depending on the shape and composition of the glass, dimensional changes after molding may exceed predictions, so the design target values are The panel was produced by aiming for the upper limit value of the standard rather than the target center value, and the panel was then trial-molded, and a number of points, including the inner surface radius, of the trial-molded panel were measured using a measuring machine called a Condoor Gauge. , check whether the inner surface radius and the dimensions at multiple points meet the predetermined target value dimensions, and if the plunger does not meet the predetermined target value dimensions, polish the surface of the plunger based on the worker's experience and intuition. It has been corrected.

This is because glass, once formed, cannot be machined to the target dimensions like metal products, so the only option is to make trial molding and modify the mold. However, a highly skilled technique was required to correct the plunger, and there remained a problem in terms of work efficiency.

In view of the above-mentioned problems of the conventional plunger correction, the present invention aims to solve the problems, and the present invention will be described in detail as follows.

In this invention, a panel is trial-molded using a plunger processed to the design target value, the surface of this panel is measured at 82 points (or 42 points), the difference between the measured value at each point and the design target value is taken out, and the plunger is A small hole is made at each point on the surface with a depth corresponding to the difference between the holes, and the surface of the plunger is polished so that the small hole disappears.

In this case, the depth of the small hole is at most about 1.0 mm,
Usually, it is within the range of 0.5 mm to 1.0 mm.

The more measurement points there are, the better the plunger surface can be obtained.

As shown in FIG. 1, a device for carrying out this invention includes a plunger 1 processed to a design target value, and a plunger 1
82 points (or 4
A computer 3 extracts the difference between the measured value of the measuring device 2, 2/ and the design target value, and outputs the difference obtained by the computer 3 to a tape. 4, a numerically controlled processing machine (for example, a drilling machine) 5 that automatically makes a small hole with a depth corresponding to the difference at each point on the surface of the plunger 1, and the surface of the plunger 10 with the small hole made is Polishing is performed using a polishing machine (not shown) in a groove where the small hole disappears, and this polishing is preferably performed under the visual observation of an operator or, if possible, automatically.

The surface of Pushinja 10 is a curved surface with the highest point at the center, and its planar shape is rectangular. This makes polishing work much easier.

As shown in FIG. 2, the measuring machines 2 and 2' have a measuring table 2a on which the object to be measured can be detachably mounted, and a measuring head 2b is provided above the measuring table 2a, and this measuring head 2b is connected to a column. The measuring head 2c is attached to the front surface of the measuring head 2c so that it can be raised and lowered via a lifting mechanism 2d such as a hydraulic or air cylinder.
At b, electric micrometer probes 2e are arranged corresponding to the 82 points (or 42 points).

Each electric micro probe 2e converts the amount of the probe's contact with the surface of the object to be measured and its retraction into an electrical quantity, and detects the amount.
This amount of electricity enters the electrical panel 2g from the switching box 2f, is amplified within the electrical panel 2g, is then converted into units of length, and is numerically displayed on a digital counter for each point. The data is converted into a tape by a converter 2h so that it can be processed by a computer.

The switching box 2f is for switching the measuring devices 2, and can be connected to several measuring devices 2 at the same time. The measured values are selectively recorded on a tape from the electric panel 2g through the A-D converter 2h.

According to the measuring device 2, it is possible to measure the uneven state of the inner surface of the panel 6, and the tape-formed data can be input into the computer 3 to calculate the difference from the design target value.

Incidentally, the measuring device 2 described above can also be used in the following manner.

That is, if you first install a master plunger on the measuring table 2a and measure its surface, adjust the value displayed on the digital counter at that time to the zero point, and measure the plunger to be measured using this as a reference, the measured value at each point can be obtained. is obtained as a value of ±α with respect to the master plunger.

The data of the values extracted in this way can be used by the computer 3 to easily determine whether the values are within the range of allowable values and to calculate to what extent they are out of range.

Note that glass is molded at high temperatures and shrinks when cooled after molding, but the curvature of the glass curved surface after cooling is usually different from the curvature of the plunger. It is necessary to correct the curvature of the plunger by inserting it.

Therefore, the measurement data of the plunger 1 and the measurement data of the panel 6 trial-molded with this plunger 1 are input into the computer 3, and compared with the design target value set and stored in the computer 3, the plunger 1 is corrected. After determining the value, the plunger 1 can be corrected by machining a small hole using the numerically controlled processing machine 5 and polishing it in the same manner.

In this case, the panel 6 is measured at the same point as the measurement point of the plunger 1 using a similar measuring device 2.

This data can also be extracted as a value of ±α with respect to the inner surface radius of the master panel with the correct shape, and the data on the plunger 1 side and its tendency can be compared on the computer 3 to find out if there is a similar tendency. A correction value can be calculated based on either data.

In this case, there is an advantage that the deformation characteristics of the glass formed as a panel can be known, and it is considered to be useful in terms of processing technology.

This invention can also be applied to correction of bottom molds for forming panels.

As explained above, according to the present invention, a plunger for forming a cathode ray tube panel can be quantitatively and accurately corrected without requiring highly skilled techniques, which is extremely useful in mold manufacturing.

[Brief explanation of drawings]

FIG. 1 is a block diagram of an implementation method of the present invention, and FIG. 2 is a schematic surface diagram of a plunger measuring device. 1 Plunger, 2, 2'... Measuring machine, 3-... Computer, 4... Tape output, 5... Numerical control processing machine, 6... Panel.

Claims (1)

[Claims] 1 The process of molding glass with a mold processed to the design target value, the process of measuring the curvature of the molded glass product at multiple points and extracting the difference from the target value, and the process of molding the glass corresponding to each of the above points. A mold for glass press molding, comprising the steps of making small holes on the surface of the mold to a depth corresponding to the difference between the two, and polishing the surface of the mold in step 1 to eliminate the small holes. Correction method.