JPH0859267A - Glass cell forming mold and its forming method - Google Patents

Abstract

PURPOSE: To enable easy production of glass cells of high accuracy by providing an inner mold freely slidably under a hollow shaft, pressurizing by feeding a fluid into the hollow part to form a glass tube between the inner mold and an outer mold which is made to oppose to the inner mold by driving the inner mold. CONSTITUTION: The shaft 1 having the hollow part 4 is cut off at its bottom end to form two cut-off parts 1a on the side faces of its bottom end, through-holes 5 are bored on the side face of the cut-off parts, respectively, and a pipe is connected to the top end of the shaft 1. Further, the projection 6 of the inner mold 2 is slidably inserted into the through-hole 5 and the outer mold 3 is arranged so that it opposes to the molding face of the inner mold 2. When a glass cell is formed, a glass tube 7 whose one end is closed is softened with heat and conveyed in a space between the inner mold 2 and the outer mold 3, and the shaft 1 to which the inner mold is set is inserted into the inside of the glass tube 7. Then, the side face of the glass tube 7 is nipped with the molding faces of the outer and the inner molds, then the hollow part 4 in the shaft 1 is filled with liquid or gas to drive the inner mold 2 by increasing or decreasing the inner pressure of the hollow part 4 to form the glass tube 7 into a glass cell.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rectangular glass cell used in a chemical analyzer, and more particularly to a rectangular glass cell for a liquid analyzer used for analyzing liquids such as water quality and body fluid.

[0002]

2. Description of the Related Art Conventionally, a method of laminating two flat glasses has been used for manufacturing a rectangular glass cell. However, in this method, when the sample was put into a glass cell, there were drawbacks such as capillary phenomenon occurring on the inner surfaces of the four corners of the laminated glass, and the sample was not stable. Therefore, in order to solve the above-mentioned drawbacks, it has been considered in recent years to heat-mold a circular glass pipe to manufacture a rectangular glass cell. As a method related to this method, for example, the invention described in Japanese Patent Publication No. 3-69852. There is.

According to the above invention, as shown in FIG. 15a, a mold 9 having a glass tube 91 coated with titanium nitride or the like is used.
2 is inserted and the gap between the inner wall of the glass tube 91 and the outer periphery of the mold 92 is reduced while heating the glass tube 91 and the mold 92 for molding. Next, when the molded glass cell 93 and the mold 92 are cooled, the outer periphery of the mold 92 becomes smaller than that of the glass cell 93 due to the difference in linear expansion coefficient. After confirming this, as shown in FIG. 15b, the mold 92 is pulled out from the glass cell 93 to finish the molding.

[0004]

However, in the invention described in Japanese Patent Publication No. 3-69852, waviness is likely to occur on the outside of the two optically required surfaces, and a polishing step is required. . Further, when molding is performed using a metal material having a linear expansion coefficient larger than that of the glass tube, and when the inner mold is taken out after the molding, using the metal material as the mold material causes a problem of fusion bonding at high temperature due to affinity with glass. is there. further,
Even if a titanium compound coating is applied to prevent fusion,
There is a risk of cracking or peeling of the coating due to the difference in linear expansion coefficient from the mold material, and the clearance between the glass tube and the mold is obtained due to the difference in linear expansion coefficient of the mold material, so the clearance is very narrow. However, it has a drawback that the two inner surfaces which are optically required when releasing the mold are easily scratched.

The object of claims 1 and 2 is to manufacture two optically necessary inner and outer surfaces of a glass cell without a polishing step, and to limit the coefficient of linear expansion of the material of the mold. SUMMARY OF THE INVENTION It is an object of the present invention to provide a glass cell molding die and a molding method capable of easily releasing a mold without causing fusion between the glass and the mold and scratches on the inner surface.

[0006]

SUMMARY OF THE INVENTION The present invention relates to a molding die for molding a glass cell, which includes a shaft having a hollow inside and two through holes facing the lower side surface.
An inner mold having protrusions slidably fitted in the through holes, a drive mechanism for the inner mold, an outer mold arranged to face the molding surface of the inner mold, and a drive device for the outer mold. A mold for molding a glass cell, which is characterized by being provided. Further, in molding a glass cell, a cavity of a shaft having a slidable inner mold is filled with a fluid or gas, and the inner mold is driven by increasing or decreasing the internal pressure of the hollow part, and the molding surface of the inner mold and And a molding surface of an outer mold which is disposed so as to face the glass cell molding method.

FIG. 1 is a conceptual diagram showing the present invention, and FIGS. 2 and 3 are sectional views showing the operation thereof. Reference numeral 1 denotes a shaft in which a cavity 4 is provided, and two shafts 1a facing each other in which the inner mold 2 is housed are provided on a side surface of a lower end portion of the shaft 1, and a through hole is formed on a side surface of each of the shafts 1a. 5 are provided. A pipe from a pump (not shown) for controlling the pressure of fluid or gas is connected to the upper end of the shaft 1.

A projection 6 provided on the back surface of the inner mold 2 is slidably fitted into the through hole 5 of the shaft 1. The cavity 4 inside the shaft 1 is a sealed cavity due to the inner surface of the shaft 1 and the end surface of the protrusion 6 on the back surface of the inner mold 2.
Full of fluid or gas. The shaft 1 is fixed on a mount of a shaft driving device (not shown). At a position facing the molding surface of the inner mold 2 in which the rear projection 6 is fitted in the through hole 5 of the shaft 1, the outer mold 3 for molding the outer surface is fixed on a mount of an outer mold driving device (not shown). There is.

In the molding using the apparatus having the above construction, first, the glass tube 7 having one end closed is heated and softened and conveyed between the outer molds 3 in the molding chamber (not shown), and the inner mold 2 is fitted therein. The shaft 1 is inserted into the glass tube 7 by a shaft driving device (not shown) (see FIG. 1). Next, an outer die driving device (not shown) is operated to press the side surface of the glass tube 7 so as to be sandwiched between the inner die 2 molding surface and the outer die 3 molding surface (see FIG. 2).

At this time, the protrusion 6 of the inner mold 2 and the cavity 4 of the shaft 1
The cavity formed by and is filled with fluid or gas, and through a pipe (not shown) connected to the upper end of the shaft 1, the inner mold 2 is pushed to the shaft 1 side by pressing the outer mold 3. It is held by applying a certain pressure so as not to move. The pressure is maintained by a pump controlling the pressure of fluid or gas connected to a pipe (not shown). Further, in a state where pressure is applied, the length from one molding surface of the inner mold 2 to the other molding surface is longer than the length of one side of the shaft 1.

After the glass is solidified by sufficiently cooling it while maintaining the pressed state, the outer die 3 is returned to the original standby position by the outer die driving device, and the outer die 3 is put into the cavity by the pump for controlling the pressure of fluid or gas. Remove the internal pressure. Further, a negative pressure is applied to the protrusion 6 on the back surface of the inner mold 2.
Is drawn into the inner cavity 4 side, and the inner mold 2 is moved toward the sharpening side 1a side of the shaft 1 by the gap 9a. By moving the inner mold 2, the molding surface is released from the inner optical surface of the glass cell. Further, since the molding surface of the inner mold 2 is pulled toward the sharpening edge 1a side of the shaft 1, a clearance is secured between the molding surface of the inner mold 2 and the inner optical surface of the glass cell by the space of the gap 9a existing at the time of molding. (See Figure 3). The shaft driving device is operated to pull out the shaft 1 from the glass cell, and the glass cell is unloaded from the molding chamber to complete the molding.

[0012]

Embodiment 1 FIGS. 4 to 8 show an apparatus used in this embodiment, FIG. 4 is a longitudinal sectional view of a molding portion, FIG. 5 is a transverse sectional view of the molding portion, and FIGS. FIG. 8 is a vertical sectional view, and FIG. 8 is a side view in which a part of the external drive device is cut away.

In FIGS. 4 and 5, reference numeral 1 is a shaft for holding the inner mold 2, and a cavity 4 is provided therein. At the lower end of the shaft 1, there is a brim 12 for receiving the bottom surface of the inner mold 2, and at the opposite side surfaces of the lower end, there are provided through holes 5. A key groove 4b is provided at the exit of the through hole 5 and a presser 4a is provided at the outer side thereof, and the key portion 2a of the inner mold 2 is inserted into the key groove 4b. There is a gap 9b between the key portion 2a and the key groove 4b, and a gap 9a equivalent to this is held by the presser 4a.
And is provided on the back surface of the molding portion 2b of the inner mold 2.

The inner mold 2 is inserted into the shaft 1 and the SU is inserted from the side surface.
A lid 8 having a cylindrical shape which is fixed to the shaft 1 with an S screw 13 to hold the inner mold 2 at the lower end, and a brim portion 12 provided at the lower end of the shaft 1 form an upper end surface and a lower end surface. It is supported. The surfaces of the shaft 1, the inner mold 2 and the lid 8 which come into contact with each other are mirror-finished in order to enhance the airtightness.
The key portion 2a and the key groove 4b are sealed by heat resistant silicon or the like. Further, a heat-resistant silicone or the like is also sealed between the inner mold 2 and a lid 8 that holds the shaft 1 from the upper end side, and between the inner mold 2 and the lower end of the shaft 1. A pipe from a pump (not shown) for controlling the pressure of fluid or gas is connected to the upper end of the shaft 1. The shaft 1 is fixed to a mount of a shaft driving device (not shown).

An outer mold 3 for molding the outer surface is fixed to the outer mold driving device 30 at a position facing the molding surface of the inner mold 2. Hereinafter, the external drive device 30 will be described with reference to FIG. The outer mold 3 is fixed to the mount 31 by a mold fixing tool 32. The mount 31 is fixed to a pedestal 35 of a linear guide 34 fixed to a molding machine main body (not shown), and an air cylinder 33 fixed to the molding machine main body is provided on an end surface opposite to the side to which the outer mold 3 is fixed. Connected,
It is provided so as to be movable in the left-right direction (in FIG. 8).

An abutment 36 is attached to the mount 31, and is adapted to abut against a stopper 37 attached to a stopper fixing tool 38 attached to the main body of the molding machine. The abutting position is adjusted by the screw part and the nut provided on the stopper fixing tool 38 and the stopper 37. For the inner mold 2 and the outer mold 3, ceramics having poor wettability with glass (for example, Cr ₂ O ₃ , AlN) are used.
Etc.) material is used.

In the molding using the apparatus having the above-mentioned structure, first, the glass tube 7 having one end closed is heated and softened, and the glass tube 7 is conveyed between the outer molds 3 in the molding chamber (not shown), and the inner mold 2 is fitted therein. The shaft 1 is inserted into the glass tube 7 by an unillustrated shaft driving device (for example, a pneumatic or hydraulic cylinder) (see FIGS. 4 and 5). Next, the outer die driving device for moving the outer die 3 is operated to press the side surface of the glass tube 7 so as to be sandwiched between the molding surface of the inner die 2 and the molding surface of the outer die 3 (see FIG. 6).

At this time, the cavity formed by the key portion 2a of the inner mold 2, the cavity 4 of the shaft 1 and the key groove 4b is filled with a fluid or a gas (for example, a gas such as N ₂ or a chemically synthesized high temperature resistant material). Is a pump that controls the pressure of fluid or gas through a pipe connected to the upper end of the shaft 1, which is filled with oil for use), and the inner mold 2 is moved to the shaft 1 side by pressing the outer mold 3. In order not to do so, a constant pressure is applied to increase the internal pressure to support the key portion 2a of the inner mold 2.

The movement amount and the pressing force of the outer die 3 which determine the size and wall thickness of the facing surface of the glass cell are determined by the outer die driving device 30.
It is determined by the position adjustment of the stopper 37 provided on the outer cylinder 3 and the pressure applied by the air cylinder 33. After pressing a certain amount, the outer mold 3 is pressed at the position set by the stopper 37.
Movement stops.

Then, the glass is solidified by sufficiently cooling it while maintaining the pressed state. After solidification, the internal pressure applied to the cavity was removed by a pump that controls the pressure of the fluid or gas, and then a negative pressure was applied to the inner mold 2
The key part 2a on the back side of the
Is moved to the shaft 1 side to release the molding surface from the inner optical surface of the glass cell, and at the same time, a clearance that makes it easy to pull out the shaft 1 is secured (see FIG. 7). Next, the outer mold 3 is returned to the original standby position by the outer mold driving device 30, and the shaft driving device that moves the shaft 1 is operated to move the glass cell to the inner mold 2.
And the glass cell is carried out from the molding chamber and the molding is completed.

Assuming that the gap 9a formed between the shaft 1 and the inner mold 2 is 0.5 mm, it is
A gap of 0.5 mm is formed between the inner mold 2 and the inner optical surface of the glass cell that face each other, and a clearance for facilitating pulling out of the shaft 1 and the inner mold 2 can be secured.

According to this embodiment, a material having poor wettability with glass, such as ceramics, can be selected for the inner mold for molding, and when a metal material or the like is used as the mold material, fusion at high temperature or In order to prevent fusion, it is possible to prevent deterioration of the optical surface of the glass cell due to cracking or peeling of the coating of titanium compound etc. applied to the mold of the metal material, and to pull out the inner mold and the shaft molded inside the glass cell. Easy to do.

[0023]

[Embodiment 2] FIGS. 9 to 14 show an apparatus used in this embodiment, FIG. 9 is a longitudinal sectional view of a molding portion, FIGS. 10 and 11 are longitudinal sectional views showing an operating state, and FIG. 12 is a piston drive mechanism. FIG. 13 is a side view of the outer die driving device, and FIG. 14 is a plan view of the outer die driving device. In this embodiment, the same components as those in the first embodiment are designated by the same reference numerals and the description thereof will be omitted. Further, the configurations of the shaft 1 and the inner mold 2 are the same as those in the first embodiment, and the description thereof will be omitted.

As shown in FIG. 9, a piston 10 is inserted in the upper end side of the shaft 1, and the outer peripheral portion of the piston 10 and the shaft 1 are inserted.
The cylinder portion 11 is sealed with a heat-resistant silicon sheet or the like. Piston 10 piston 10
Is connected to a drive mechanism 13 for driving.

The drive mechanism 13, as shown in FIG. 12, is a support plate 1 fixed to the upper part of a molding machine (not shown).
A guide 15 is fixed to the guide 4, and a moving base 16 is attached on the guide 15 so as to be vertically movable. The moving base 16 has a ball screw 17 for moving the moving base 16 up and down.
Is attached, and the upper end of the ball screw 17 is connected to a motor 19 fixed by a motor pedestal 18 fixed to the support plate 14. Further, the lower end of the ball screw 17 is fixed to the support plate 14 by a retainer 20. A piston retainer 21 is provided on the movable base 16.
The piston 10 is fixed by.

The external drive unit 30 is shown in FIGS.
, The outer mold 3 is mounted on the mount 3 by the mold fixing tool 32.
It is fixed at 1. The mount 31 is fixed to a pedestal 35 of a linear guide 34 which is fixed to the main body of the molding machine. The motor 41 is fixed to the main body of the molding machine, and the ball screw 40 is attached to the shaft. The other end of the ball screw 40 is supported by a screw retainer 42 fixed to the molding machine body. A guide 39 that moves by the rotation of the screw is installed on the ball screw 40 and is fixed to the mount 31.

The operation of this embodiment will be described below. Until the glass tube 7 whose one end is closed is heated and softened and conveyed between the outer dies 3 in a molding chamber (not shown), and the shaft 1 into which the inner dies 2 are fitted is inserted into the glass tube 7 and molded. Since the process is the same as that of the first embodiment, the description thereof will be omitted. During molding, the cavity formed by the key portion 2a of the inner mold 2, the cavity 4 of the shaft 1, the key groove 4a, and the piston 10 contains a fluid or a gas (for example, a gas such as N ₂ or a chemically synthesized high temperature resistant material). Oil, etc.) is filled.

First, the motor 19 of the drive mechanism 13 connected to the piston 10 rotates the ball screw 17 to lower the moving base 16 so that the inner mold 2 is not moved to the shaft 1 side by the pressing of the outer mold 3. Then, the piston 10 is pushed downward to increase the pressure in the cavity to support the key portion 2a of the inner mold 2 (see FIG. 10). Here, the pressure applied to the cavity and the key portion 2a of the inner mold 2 is set by the descending amount of the piston 10, and the descending amount is determined by the moving amount of the moving pedestal 16 by the rotation of the motor 19 and the ball screw 17.

The amount of movement of the outer die 3 and the pressing force that determine the dimensions and wall thickness of the facing surfaces of the glass cell are determined by the setting of the motor 41 provided in the outer die driving device 30. For example, if a servo motor or the like is used as the motor 41, position control, pressing force control, speed control, etc. can be performed, and after pressing a certain amount of the glass cell, the position is held at a pressing force of 0,
It is possible to obtain a desired size of the opposite surface of the glass cell.

The glass is solidified by sufficiently cooling it while maintaining the pressed state. After solidification, the motor 19 of the drive mechanism 13
The rotation of the ball screw 17 moves the moving pedestal 16 upward to move the piston 10 upward, and removes the internal pressure applied to the cavity. Furthermore, piston 1
Negative pressure is applied to the cavity by pulling up 0,
Pull the key portion 2a on the back surface of the inner mold 2 toward the inner cavity 4 side,
The inner mold 2 is moved to the shaft 1 side to release the molding surface from the inner optical surface of the glass cell, and at the same time, a clearance is secured to facilitate the pulling out of the shaft 1 (see FIG. 11).

Next, the outer die 3 is returned to the original standby position by the outer die driving device 30, the drive mechanism for moving the shaft 1 is operated to pull it out from the glass cell, and the glass cell is carried out from the molding chamber. Finish molding. Assuming that the gap 9a formed between the shaft 1 and the inner die 2 is 0.5 mm, the inner diameter of the inner die 2 and the inner optical surface of the glass cell, which are opposed to each other, are less than 0. A gap of 5 mm is created,
A clearance for making it easy to pull out the shaft 1 and the inner mold 2 can be secured.

According to this embodiment, the same effect as that of the first embodiment can be obtained, and the vertical movement of the piston can be controlled by the rotation of the motor and the ball screw, etc., and a pump for pressurizing and depressurizing the fluid can be provided outside the molding machine. Since it is not necessary, the molding machine body can be downsized. Further, since the pressing operation and the movement amount of the outer die can be finely controlled by the motor or the like, it is possible to obtain a glass cell having highly accurate dimensions and wall thickness.

[0033]

According to the effects of claims 1 and 2, the optically necessary two inner surfaces and the outer surface of the glass cell can be manufactured without a polishing step, and fusion between the glass and the mold occurs. Without doing so, the mold release without scratches on the inner surface can be easily performed, and a highly accurate glass cell can be molded.

[Brief description of drawings]

FIG. 1 is a conceptual diagram showing the present invention.

FIG. 2 is a cross-sectional view showing the operation of FIG.

FIG. 3 is a cross-sectional view showing the operation of FIG.

FIG. 4 is a vertical sectional view showing the first embodiment.

FIG. 5 is a cross-sectional view showing the first embodiment.

FIG. 6 is a vertical sectional view showing the first embodiment.

FIG. 7 is a vertical cross-sectional view showing the first embodiment.

FIG. 8 is a partially cutaway side view showing the first embodiment.

FIG. 9 is a vertical sectional view showing a second embodiment.

FIG. 10 is a vertical sectional view showing a second embodiment.

FIG. 11 is a vertical sectional view showing a second embodiment.

FIG. 12 is a side view showing a second embodiment.

FIG. 13 is a side view showing a second embodiment.

FIG. 14 is a plan view showing a second embodiment.

15A and 15B are cross-sectional views showing a conventional example.

[Explanation of symbols]

 1 Axis 2 Inner Mold 3 Outer Mold 4 Cavity 5 Through Hole 6 Projection 7 Glass Tube 9a Gap

Claims (2)

[Claims] 1. A molding die for molding a glass cell, wherein a shaft having a cavity therein and having two through holes facing the lower side surface is formed, and a projection part slidably into each of the through holes. A mold for molding a glass cell, comprising an inner mold to be fitted, a drive mechanism for the inner mold, an outer mold arranged to face a molding surface of the inner mold, and a driving device for the outer mold. . 2. When molding a glass cell, a cavity of a shaft having a slidable inner mold is filled with a fluid or gas, and the inner mold is driven by increasing or decreasing the inner pressure of the hollow part, and the inner mold is molded. A glass cell molding method, comprising molding with a surface and a molding surface of an outer mold disposed opposite to the surface.