JPH05294649A - Glass molding apparatus - Google Patents

Abstract

PURPOSE:To provide the subject apparatus designed to make ready connection/ separation for top force unit and bottom force unit for the purpose of realizing process automation in the press molding of a glass material, also designed to ensure the socket and spigot jointing for these units and their conveyance to be stabilized. CONSTITUTION:In a mold 10 made up of (A) a bottom force unit 1 provided with a lower part chase 2 and a lower mold 3 and (B) a top force unit 11 provided with an upper chase 12 and an upper mold 13, these units are mutually connected through socket and spigot joints 2a,12a, and a negative pressure chamber-forming element 30 with a negative pressure chamber 30a is provided on the outer periphery of the lower part chase 2 of the bottom force unit 1 and a retracting lever 31 is suspendedly provided at the fitting part 12b on the upper part chase 12 of the top force unit 11, and a suction piping 32 is connected to the negative pressure chamber 30a; the chamber 30a is set at a negative pressure in such a state as to advance the lever 31 via a retracting hole 33 into the chamber 30a; then, a force acts in such a direction that the lever 31 is retracted into the chamber due to the resulting negative pressure suction force, thus exerting a clamping force in such a direction as to bring the top force unit 11 into press contact with the bottom force unit 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a glass forming apparatus for forming glass products such as lenses.

[0002]

2. Description of the Related Art In manufacturing precision optical glass such as lenses, a method of molding by a pressing means in a state where a glass material is melted or softened has become popular in recent years. That is, as a forming die, a forming die including a body die and a lower die and an upper die guided by the body die is provided, a forming portion is formed between the upper and lower dies, and a glass material is placed in the forming portion. By setting and heating the entire molding die, the glass material in the molding part is softened, and the glass material is press-molded by pushing up the lower mold or lowering the upper mold.

Here, when actually manufacturing a lens or the like as a molded product by press-molding a glass material, for example, the following steps are performed. First, with the upper mold and the lower mold separated, set the glass material in the molding part and connect the upper mold and the lower mold, then heat the glass material in the molding part to soften it, and then press it. Perform molding. When the press molding is completed, the molded product is cooled, the upper mold and the lower mold are separated, and the molded product is taken out. Further, after taking out this molded product, a new glass material is set in the molding section, and the next glass material is molded in the same manner as described above.

[0004]

By the way, in order to automate the press forming process performed according to the above-mentioned steps,
As a matter of course, it is necessary to provide a press-molding means consisting of a punch and a die, and in order to make it possible to set the glass material and take out the molded product, the upper die and the lower die are separated by an appropriate handling means. They must be connected or connected, and the glass material must be set and the molded product should be taken out by using a pick and place means or the like. In order to prevent these handling means and pick-and-place means from interfering with the press-molding means, at least the site where the glass material is set and the molded product is taken out is different from the site where the press-molding means is provided. Will be installed in the position. Therefore, it is necessary to move the forming die while the lower die and the upper die are connected in the meantime.

In performing both the work of setting the glass material and taking out the molded product, the lower mold and the upper mold must be separated, but the upper mold is lifted by the handling means to separate from the lower mold. It's also the easiest to do. For setting the glass material and taking out the molded product, a pick-and-place means is used, and the pick-and-place means is moved laterally to set the glass material or take out the molded product. Is rational. For this purpose, it is convenient to connect the upper mold and the lower mold by means such as inro cage fitting.

However, when the upper mold and the lower mold are connected by the cage fitting, the stability in the connected state cannot be sufficiently obtained. Therefore, when the molding die is transferred, there is a disadvantage that the upper die particularly shakes, rattles, or shifts, resulting in a considerable influence on the processing accuracy of the glass material. In order to stabilize the upper mold, it is possible to use, for example, a locking action using a spring action or a magnet, but it is necessary to heat the glass material to about 500 ° C. at the time of molding the glass material. Since the spring force and the magnetic force change due to the influence, it is impossible to exert a stable locking action. Further, if the contact area of the inro cage fitting portion is increased, the stability in the connected state of the upper die and the lower die is improved. However, if such a configuration is adopted, the barrel die becomes thicker and The heating performed from outside the mold cannot be performed efficiently.

The present invention has been made in order to solve the problems of the prior art as described above, and its purpose is to make it possible to easily connect / separate an upper mold to a lower mold, An object of the present invention is to provide a glass forming apparatus capable of holding the upper mold in a stable state when the mold and the lower mold are conveyed.

[0008]

[Means for Solving the Problems] The above-mentioned object is achieved.
For the purpose of the present invention, the lower mold is installed in the lower body mold part.
The lower mold unit and the lower body part can be attached and removed by mating Inro
After mounting the upper mold inside the upper body part that is connected to
Molding that consists of a mold unit and is formed between the upper and lower mold parts
Set the glass material on the part and heat it, and add it between the upper and lower molds.
Pressing a glass material by applying pressure.
Either the lower mold unit or the upper mold unit
A negative pressure chamber is formed on the other side, and the other side can be inserted into and removed from this negative pressure chamber.
Is provided with a negative pressure acting member, and this negative pressure acting member is
Insert into negative pressure chamber and apply negative pressure to negative pressure chamber
By sucking the action member, the lower mold unit and the upper mold unit
The feature is that the mold is clamped to the knit.
It is what

[0009]

Since the forming die is composed of the lower die unit and the upper die unit, each of which is composed of the body die and the forming die, and the upper and lower body die portions are configured to fit in the cage, the upper die unit Can be easily separated from the lower mold unit only by lifting. When the upper mold unit is separated from the lower mold unit, a glass material is set on the lower mold, and then the upper mold unit is lowered to connect with the lower mold unit. In this state, the forming die is moved to a portion where the forming process is performed, but the negative pressure acting member is inserted into the negative pressure chamber when the upper die unit is connected to the lower die unit. When the negative pressure chamber is placed in a negative pressure state, a force acts in the direction in which the negative pressure acting member enters the negative pressure chamber, and as a result, the molding die becomes stable and the upper die unit moves unintentionally during its movement. There is no risk of misalignment or displacement.

Here, when the glass material is molded, in order to prevent the molding die from being heated due to the heating of the glass material to form an oxide film on the surface portion of the molding portion, The atmosphere is replaced, but in order to promote this atmosphere replacement, a vacuum suction means is connected to the mold, and the pipe from this vacuum suction means is connected to the negative pressure chamber. The suction force of the negative pressure acting member can be exerted.

When the upper mold unit is separated from the lower mold unit, outside air containing oxygen may enter during this period. In order to prevent such a situation, the negative pressure acting member is formed with an outflow part of the inert gas so as to surround the body part of the upper mold unit, and when the upper mold unit is separated from this outflow part. If the inert gas is allowed to flow out, an inert gas curtain is formed, and the outside air containing oxygen can be prevented from entering between the lower mold and the upper mold as much as possible.

[0012]

Embodiments of the present invention will now be described in detail with reference to the drawings. First, FIG. 1 shows the overall structure of the press molding apparatus. In the figure, 1 denotes a lower mold unit and 11 denotes an upper mold unit, and the lower mold unit 1 and the upper mold unit 11 form a molding die 10. The lower mold unit 1 has a lower body part 2 and a lower mold 3 inserted into the lower body part 2, and a heater 4 is mounted around the lower body part 2. Has been done. Upper mold unit 11
Similarly to the lower mold unit 1, an upper body mold portion 12 and an upper molding die 13 inserted into the upper body mold portion 12 are provided, and a heater 14 is provided on the outer peripheral portion of the upper body mold portion 12. Is installed. A reduced diameter male imprint portion 2a is formed on the upper portion of the lower body portion 2, and a female imprint portion 12a is formed at the lower portion of the upper body portion 12 to form both male and female imprint portion 2a. , 12a are fitted in the cage, so that the upper mold unit 11 is connected to the lower mold unit 1. A taper wall is formed at the upper end of the male in basket portion 2a for smooth and reliable engagement of the in cage.

The lower molding die 3 and the upper molding die 13 are provided with mold surfaces 3a and 13a, respectively.
The mold surface 13a of the lower mold 3 extends to a position where the mold surface 13a of the lower mold 3 is inserted. Therefore, the mold surface 3a of the lower mold 3, the mold surface 13a of the upper mold 13, and the lower mold 1 are both formed. The portion between the mold surfaces 3a and 13a becomes the molding portion 20, and the glass material 21 is set in the molding portion 20. Then, while the glass material 21 is heated and the upper mold 13 is brought into contact with the upper mold pressing means 22, the push-up plunger 23 is projected from the lower position of the lower mold 3 by the driving means such as a cylinder. By doing so, the glass material 21 is press-molded and the lens is manufactured. In the figure, reference numeral 24 is for holding the lower molding die 3 of the lower mold unit 1 so as not to deviate from the lower body mold portion 2 and for positioning the lower molding die 3 at the uppermost end position and the lowermost end position. Showing the positioning rod of this positioning rod 2
Reference numeral 4 is inserted into an insertion hole 25 provided so as to penetrate the peripheral body portion of the lower molding die 3. Therefore, in the lower molding die 3, the positioning rod 24 has the upper end portion 25a and the lower end portion 25b of the insertion hole 25.
It can be displaced in the vertical direction to a position where it comes into contact with.

In automating the whole process from setting the glass material 21 in the molding unit 20 to taking out the lens after the processing is completed, at least the molding die 10 is set to the glass material 2
A load / unload mechanism is arranged at a portion where 1 is set or a lens is taken out after the molding is completed, and a press molding means is arranged at a portion where molding is performed. For this reason, the mold 10 must be conveyed by a conveyor or other means. In order to easily set the glass material 21 in the molding part 20 and take out the lens, the connection between the upper mold unit 11 and the lower mold unit 1 is made up of female and male parts formed in the upper and lower body mold parts 2, 12. It is configured to be carried out by fitting the imprints by both imprinting parts 2a and 12a. This significantly simplifies the operation of the means for handling the upper mold unit 11. However, such a connecting mechanism alone is extremely simple and unstable, and the molding die 10
There is a risk that the upper mold unit 11 may shake, rattling, or be displaced due to vibrations or the like that occur during the transportation of the above. Therefore, in order to stabilize the connection between the lower mold unit 1 and the upper mold unit 11, a mold clamping mechanism is provided.

As the mold clamping mechanism, as is clear from FIG. 2, four negative portions are provided on the outer peripheral portion of the lower body mold portion 2 of the lower mold unit 1 integrally with or separately from the lower body mold portion 2. Pressure chamber forming body 30 and upper body part 1 of upper mold unit 11
2 and the pulling rod 31 vertically installed on the mounting portion 12b.
Composed of and. A negative pressure chamber 30a is formed inside the negative pressure chamber forming body 30, and a suction pipe 32 is formed in the negative pressure chamber 30a.
Is connected, and a lead-in hole 33 is formed at a position facing the negative pressure rod 31. The negative pressure acting hole 32 has a diameter slightly larger than the outer shape of the pulling rod 31, and the negative pressure chamber 30a is negatively pressured while the negative pressure acting rod 31 is inserted from the pulling hole 33 into the negative pressure chamber 30a. In this state, due to the negative pressure suction force, a force acts in the direction in which the negative pressure rod 31 is drawn into the negative pressure chamber 30a, and a force acts in the direction in which the upper mold unit 11 is pressed against the lower mold unit 1. , It is configured to exert the mold clamping force. Further, when the negative pressure acting rod 31 is fitted into the pull-in hole 33, the pull-in hole 33 is formed with a pull-in portion 33a for pulling in the negative pressure acting rod 31.

By the way, when the glass material 21 is press-molded, it is necessary to heat the entire molding die 10 by the heaters 4 and 14 to raise the temperature of the glass material 21 to about 500.degree. When the glass material 21 is heated in a gas containing oxygen, an oxide film is formed on the mold surfaces 3a and 13a forming the molding part 20. In order to prevent such a situation, the inside of the molding unit 20 is replaced with an inert gas atmosphere. For this,
The lower mold unit 1 and the upper mold unit 11 are provided with gas flow paths 5 and 15, respectively. The gas flow path 5 in the lower mold unit 1 has a passage 5a provided in the lower barrel mold portion 2, and this passage 5a is opened to an insertion hole 25 provided in the lower molding die 3. In addition, the insertion hole 25 in the lower mold 3
A groove 5b is provided in an outer peripheral portion of a portion between the forming position of the mold and the mold surface 3a, and a gas passage is formed between the groove 5b and the inner peripheral surface of the lower body mold portion 2. The gas flow passage 15 on the upper die unit 11 side has a passage 15a provided in the upper barrel die portion 12, and this passage 15a opens into an annular groove 15b formed in the peripheral barrel portion of the upper molding die 13. Then, the forming portion of the annular groove 15b on the outer peripheral surface of the upper molding die 13 and the die surface 1
A groove 15c is provided in a portion between the groove 3c and 3a, and a gas passage is formed between the groove 15c and the inner peripheral surface of the upper body mold portion 13.

Passages 5a, 15 in the gas flow paths 5, 15
Nitrogen gas as an inert gas can be supplied to a, and in order to perform the atmosphere replacement more efficiently and completely, one of the gas flow paths 5 and 15, usually the lower unit 1 Nitrogen gas is supplied to the gas passage 5 on the side of the upper mold unit 11, and the gas passage 15 on the side of the upper mold unit 11 is connected to a negative pressure source.
A negative pressure is applied to the inside of the molding unit 20. Therefore, this negative pressure source is used to bring the inside of the negative pressure chamber 30a into a negative pressure state so that the suction force is exerted.

In order to automate the entire process from setting the glass material 21 in the molding unit 20 through press molding to taking out the lens after processing, as shown in FIG. 3, a loader / unloader station 40 is used. A heating / cooling station 41 and a press molding station 42 are provided, the molding die 10 is set in the loader / unloader station 40, and the glass material 21 is set in the molding unit 20.
Next, the heating / cooling station 41 is moved to soften the glass material 21 to an extent necessary for press-forming, press-molded in the press-molding station 42, returned to the heating-cooling station 41 and cooled, The press-molded lens is taken out by the loader / unloader station 40, and a new glass material 21 is set.

The loader / unloader station 40 has a handling means 43 for moving the upper die unit 11 up and down, and a pick and place means 44 for setting the glass material 21 and taking out the lens after molding. It is provided. Further, when the glass material 21 is set or the lens is taken out by the pick-and-place means 44, a pusher 23 for raising the lower mold 3 is provided in order to facilitate the work. .. In the press molding station 42, a plunger 23 for pushing up the lower molding die 3 is provided so as to be able to move up and down, and an upper die pressing means 22 for pressing the upper die unit 11 from above is provided so that it can be raised and lowered. ..

The present embodiment is constructed as described above. First, the molding die 10 is placed in the loader / unloader station 40 and the glass material 21 is set. In this work, as shown in FIG. 4, the upper mold unit 11 is lifted to move the mold surface 3 of the lower mold 3 in the lower mold unit 1.
Open a. Then, the glass material 21 is set on the mold surface 3a, and then the upper mold unit 11 is lowered. As a result, the negative pressure rod 31 is first fitted into the lead-in hole 33 in the negative pressure chamber forming body 30. Here, since the drawing-in hole 33 is provided with the inviting portion 33a, even if the upper mold unit 11 is slightly displaced from the lower mold unit 1, the negative pressure rod 31 is The position of the upper mold unit 11 is adjusted when the upper mold unit 11 is fitted into the lead-in hole 33.
An aligning action is exerted on the lower mold unit 1. Then, when the upper die unit 11 is further lowered, the female intaglio portion 13a formed on the barrel die portion 12 is fitted into the male inlay portion 2a of the lower barrel die portion 2. Thus, since the upper and lower units 1 and 11 are aligned when the negative pressure rod 31 is fitted into the lead-in hole 33, the seal fitting is performed extremely smoothly and reliably.

When the molding die 10 is assembled as described above, first, the atmosphere of the molding portion 20 in which the glass material 21 is arranged is replaced. For this purpose, the lower mold unit 1
The nitrogen gas is supplied to the gas passage 5 on the side, and the gas passage 15 of the upper mold unit 11 is connected to a negative pressure source to suck the air in the molding unit 20. As a result, the atmosphere replacement is performed extremely efficiently and completely. At the same time, the suction pipe 32 connected to the negative pressure chamber 30a is connected to a negative pressure source to make the inside of the negative pressure chamber 30a negative pressure. As a result, a negative pressure acts on the negative pressure action rod 31, and a force acts in the direction of being drawn into the negative pressure chamber 30a, so that the upper mold unit 11 is brought into pressure contact with the lower mold unit 1 and a so-called mold clamping force is applied. By exerting, the upper and lower units 1 and 11 are firmly connected.

When the atmosphere replacement in the molding section 20 is completed,
The communication between the gas flow path 15 and the negative pressure source is cut off, the heating / cooling station 41 is moved to, and the heaters 4 and 14 are operated to heat the entire molding die 10 to the molding portion 20. The set glass material 21 is softened to a state where it can be press-molded. After that, when the glass material 21 is softened to a press-moldable state, the molding die 10 is moved to the press-molding station 42. Then, the upper die pressing means 22 installed in the press forming station 42 is operated to bring it into contact with the upper portion of the upper die unit 11. As a result, the upper mold unit 11 and the lower mold unit 1 are firmly connected and fixed. In this state, by pushing up the plunger 23, the glass material 21 is press-molded to form a lens.

Here, in order to transfer the molding die 10 to the heating / cooling station 41 and to transfer it from the heating / cooling station 41 to the press molding station 42, the molding die is conveyed by a conveying means such as a conveyor. Although vibration or the like occurs during this conveyance, a mold clamping force is exerted between the upper mold unit 11 and the lower mold unit 1 by drawing the negative pressure rod 31 into the negative pressure chamber 30a,
The connection between the upper mold unit 11 and the lower mold unit 1 is stable, and there is no inconvenience that the upper mold unit 11 shakes, rattles, or shifts with respect to the lower mold unit 1 during conveyance.

When the press molding is completed, the upper die pressing means 2
2 is separated from the upper mold unit 11, and the plunger 2
3, the molding die 10 is moved to the heating / cooling station 41 for cooling, and then to the loader / unloader station 40.
By maintaining the negative pressure inside 0a, the connection between both units 1 and 11 is stabilized. As a result, after the upper die unit 11 is connected to the lower die unit 1, the molding die 10 is transferred from the loader / unloader station 40 to the press molding station 42 via the heating / cooling station 41, and vice versa. The molding die 10 can always be maintained in a stable state during the entire moving process until it is returned to the loader / unloader station 40.

As described above, in order to soften the glass material 21, the entire molding die 10 is heated. Therefore, the molding die has an extremely high temperature of about 500 ° C. Composed of pressure,
Since a spring, a magnet, or the like that is affected by heat is not used, the operation can be stabilized. Also,
Since this mold clamping mechanism stabilizes the connection state of the upper mold unit 11 to the lower mold unit 1, the body mold parts 2, 1
It is not necessary to increase the thickness of No. 2 to widen the joining area between the two, and it is possible to efficiently heat the molding die 10 performed by the heaters 4 and 14 from the outer peripheral side of the body mold portions 2 and 12.

5 and 6 show a second embodiment of the present invention. In this embodiment, a negative pressure chamber 50a is provided inside.
It is shown that the negative pressure chamber forming body 50 and the negative pressure acting member 51 having the above are formed in an annular shape. The suction pipe 52 is connected to the negative pressure chamber 50a and the drawing-in hole 53 is formed as in the first embodiment described above, but the negative pressure acting member 51 is formed in an annular shape. Therefore, the lead-in hole 53 is also formed in an annular shape. Further, the negative pressure acting member 5 is inserted in the drawing hole 53.
A taper-shaped inviting portion 53a is formed at the inlet portion of 1. Further, the negative pressure acting member 51 is formed with an annular gas outflow passage 54 opening at the lower end thereof. A nitrogen gas supply pipe 55 is connected to the gas outflow passage 54.

By adopting such a configuration,
In order to set the glass material 21 in the molding section 20 and to take out the lens after molding, the upper mold unit 1
1 is separated from the lower mold unit 1, the gas outflow passage 5
By ejecting nitrogen gas from the upper mold unit 4, the upper mold unit 13 in the upper mold unit 11 and the lower mold unit 3 in the lower mold unit 1 are arranged only at different positions in the vertical direction.
Is exposed to the outside, but at this time, since a nitrogen gas curtain surrounding it is formed, the mold surfaces 3a, 13a of both the molds 3, 13 are held so as not to touch the outside air as much as possible. This can prevent the mold surfaces 3a and 13a from being oxidized as much as possible. Moreover, since the nitrogen gas supplied from the nitrogen gas supply source for performing the atmosphere replacement can be used, even if such a nitrogen gas curtain is formed, the size of the special apparatus becomes large. Inconvenience such as does not occur.

[0028]

As described above, according to the present invention, the lower mold unit and the upper mold unit are detachably connected by the cage fitting, so that they can be easily attached and detached by the handling means such as a robot. Moreover, since both of them are made stable by the negative pressure chamber and the negative pressure acting member that is removably fitted in the negative pressure chamber,
Even if the forming die is transported, the upper die unit does not move or move while moving, so that the glass material is set in the forming die, and the glass material is heated to soften and press-form. It is extremely convenient for automating all the work from cooling the molded product by press working to taking it out.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a press molding apparatus showing a first embodiment of the present invention.

FIG. 2 is a plan view of FIG.

FIG. 3 is a process explanatory diagram in the press molding apparatus.

FIG. 4 is a cross-sectional view of the press molding apparatus showing an operating state different from that in FIG.

FIG. 5 is an external view of a negative pressure acting member according to a second embodiment of the present invention with a part thereof cut away.

6 is an external view of a press molding apparatus equipped with the negative pressure acting member of FIG.

[Explanation of symbols]

 1 Lower Mold Unit 2 Lower Body Mold Part 3 Lower Mold Mold 10 Mold Mold 11 Upper Mold Unit 12 Upper Body Mold Part 13 Upper Mold Mold 15 Gas Flow Path 20 Molding Part 21 Glass Material 30,50 Negative Pressure Chamber Former 30a, 50a Negative pressure chamber 31 Negative pressure acting rod 32,52 Suction pipe 33,53 Inlet hole 33a, 53a Introducing part 40 Loader / unloader station 41 Heating / cooling station 42 Press forming station 51 Negative pressure acting member 54 Gas outflow passage 55 Nitrogen gas pipe

Claims (2)

[Claims] 1. A lower mold unit in which a lower molding die is mounted in a lower barrel mold portion, and an upper mold unit in which an upper molding die is mounted in an upper barrel mold portion removably connected to the lower barrel mold portion by a seal fitting. A glass material is set in a molding part formed between the upper and lower mold parts and heated, and a pressing force is applied between the upper and lower mold parts to press-mold the glass material. A negative pressure chamber is formed in one of the mold unit and the upper mold unit, and a negative pressure acting member that is removably fitted into the negative pressure chamber is provided in the other, and the negative pressure acting member is provided in the negative pressure chamber. Glass molding characterized in that the mold is clamped between the lower mold unit and the upper mold unit by inserting a negative pressure into the negative pressure chamber to suck the negative pressure acting member. apparatus. 2. The negative pressure acting member on the upper mold unit side,
It is installed in a state of surrounding the upper body part, and when the upper mold unit is separated from the lower mold unit at the lower end of this negative pressure acting member, the upper and lower mold parts are cut off from the outside air by letting out an inert gas. The glass forming apparatus according to claim 1, wherein an outflow portion of the inert gas for forming the inert gas curtain is formed.