JPS62265136A - Hot press forming machine - Google Patents

Abstract

PURPOSE:To prevent the deterioration of the lifting accuracy of an upper die and to improve the accuracy of press forming of a glass stock by providing a lifting guide part for the upper die to the outside of a press forming chamber at the time of heating and softening the glass stock by the upper and lower dies of a high temp. and press- forming the same to a lens. CONSTITUTION:The glass stock 16 is heated and softened by the lower die 23 and upper die 22 heated to the high temp. by heaters 18, 20 and is pressed by lens spherical face parts 22, 23 of the end faces of both dies, by which the glass stock is formed to the lens. The lifting sliding device for the upper die 21 is deformed with the high temp. by said heating, by which the vertical lifting accuracy of the upper die 21 is deteriorated and the upper die fails to descend exactly with respect to the hole part 19 of the lower die 17. A press shaft 28 for lifting of the upper die 45 is provided to the outside of the press forming chamber 26 and the press shaft 28 and the high- temp. forming chamber 26 are thermally insulated by a thermally insulating elastic O-ring 34 made of rubber, etc., in order to prevent the same. Since the deformation of a shaft holder 31, etc., of the press shaft 28 by heat is obviated, the vertical lifting of the press shaft 28 by a cylinder 29 is exactly executed and the upper die 21 makes pressurizing motion exactly relative to the lower die 17.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates to a hot press molding machine for molding glass, lenses, and the like.

2. Description of the Related Art A conventional hot press molding machine of this type has a structure as shown in FIG.

That is, a plurality of columns 2 are supported upright on a base 1.
An upper plate 3 is fixedly supported in a gate shape on the upper part of the upper plate 3, and an intermediate plate 4 that can be slid up and down using the support column 2 as a guide is arranged in the middle part, and is fixed to the center part of the upper plate 3. By connecting the drive rod 6 of the cylinder 5 and this intermediate plate 4, it can be slid up and down. The molding process is carried out by fixing and supporting the molding press part 7 in the center of the intermediate plate 4 and the molding receiving part 8 on the base 1 so as to face each other. In addition, since the molding process is carried out at high temperatures, it is necessary to carry out the process in an inert gas atmosphere to prevent oxidation. , an inert gas such as N2 gas was fed through the gas inlet 10 to perform the molding process.

Problems to be Solved by the Invention However, with such a structure, when the heaters 11 and 12 built into the molding push part 7 and the molding receiving part 8 are heated,
The intermediate plate 4 and the base 1 are deformed due to thermal expansion and sliding becomes hard, resulting in chatter and a significant loss of vertical lifting accuracy. Particularly when molding glass materials, etc., the heaters must be heated to a high temperature until the glass material reaches its softening point (approximately 600°C). Also, on the intermediate plate 4 and base 1,
Holes 15 and 16 through which cooling water flows are provided to prevent heat conduction. However, when molding is performed continuously, it is not completely cooled, and heat is accumulated due to radiant heat, etc., and the base 1, intermediate plate 4, and support column 2 are gradually heated and deformed due to thermal expansion. A problem occurs. In addition, when molding glass materials, in order to maintain molding accuracy, pressure is maintained even after molding at the hardening point (approximately 3
There was a problem in that the temperature had to be lowered until it reached 00° C., and that it took a long time to wait because the heater was turned off and allowed to cool naturally.

Therefore, the present invention actively prevents heat conduction in the molding heating section, and also makes it possible to ensure the accuracy of raising and lowering the molding press shaft even if the surrounding area accumulates some heat due to radiant heat. It also shortens the time required for the temperature to drop after molding.

A further means for solving the problems and a technical means of the present invention for solving the above-mentioned problem is to include the molding heating part in the chamber, and separately provide a lifting guide part outside the chamber to maintain the molding lifting precision. It is something that Further, the sliding joint between the chamber containing the heating element and the press shaft for performing the molding is arranged to be in contact with each other via a ring-shaped elastic body held by a flange made of a heat insulating material. Further, the press shaft is provided with a cooling means that flows through the shaft core portion, and the molded receiving portion is provided with a cooling means that discharges the entire lower surface of the base attachment side from a nozzle opening that protrudes from below. Further, in order to lower the temperature after molding, a cooling means by discharging inert gas is provided near a part of the heater.

For production The effect of this technical means is as follows.

In other words, the chamber undergoes thermal deformation by including the molding heating part in the chamber, but the guide part that slides the molding press shaft up and down, which affects the molding accuracy, is separated from the chamber and subjected to thermal deformation. By performing this at a location where there are no bumps, the forming press shaft can be moved up and down with high precision. In addition, the influence of heat received by the press shaft from the heated chamber is through the ring-shaped elastic body held by the flange made of heat insulating material, so there is almost no heat transfer from the chamber, and the mechanical thermal deformation of the chamber It is not affected by any force at all. Moreover, since it slides through a ring-shaped elastic body, it also has a sealing effect.

Further, the thermal influence of the molding press shaft itself can be completely prevented from being conducted by letting cooling water flow through the shaft core of the molding press shaft.

In addition, heat conduction at the molded receiver can be completely prevented by cooling the entire lower surface of the molded receiver to which the base is attached through the protruding nozzle opening.

As a result, even if the molding heating section reaches a high temperature, heat conduction can be interrupted, and the molding press shaft can perform highly accurate molding without being affected by heat.

In addition, when lowering the temperature of the heating part after molding, it is possible to rapidly cool the heater part by discharging cooled N2 gas through a small hole machined from the inside to the outside of the heater part, which greatly shortens the molding cycle. It can shorten the time.

Embodiment Hereinafter, one embodiment of the present invention will be described based on the attached drawings. FIG. 2 is an enlarged longitudinal sectional view of the forming press processing section.

Reference numeral 16 denotes a glass lens material to be molded, which is put into a hole 19 of a lower mold 170 heated by a heater 18 and heated by heat conduction. When the temperature of the glass lens material 16 is raised to the softening point, the upper mold 21 heated by the heater 20 is lowered, molding pressure is applied, and the lens spherical parts 22 and 23 of the upper mold and the lower mold are transferred. The lens molding process is performed by. At this time, it is important to note that unless the upper mold 21 is vertically and precisely lowered, the optical axes of both spherical surfaces of the molded lens will be deviated or tilted. FIG. 1 is a longitudinal sectional view of a hot press molding machine according to an embodiment of the present invention, in which a molding receiving part 25 is fixed on a base 24, and a chamber 26 is similarly attached to the base 24 so as to surround this molding receiving part 25. It is fixed. Reference numeral 27 denotes a molding press part, which is fixed to the lower end of the press shaft 28 and is arranged in the chamber so as to face the molding receiving part 25 . Reference numeral 28 denotes a press shaft for performing molding, which passes through the upper part of the chamber 26 and is connected at its upper end to a cylinder 290 and a drive rod 3Q, so that it can slide up and down. Further, the press shaft 28 is firmly supported by a shaft holder 31 and is slidably guided with high precision above the chamber 26 by a linear bearing portion 33 attached to a rational frame 32 fixed to the base 24. The point of contact between this press shaft 28 and the upper part of the chamber 26 is still an elastic body.
Although it is sealed by a ring 34, this Q l/
The flange 52 made of a heat insulating material holding the ring and the press shaft are fitted with a gap and are not in contact with each other. Therefore, even if the chamber itself is slightly deformed due to heat, the press shaft 28 is not affected and mechanical precision can be maintained. Also, heat transfer from the chamber is extremely low. Furthermore, even if the heater 35 of the molding press part 27 reaches a high temperature, cooling water is injected from a into the press shaft 28 through the heat insulating material 36 and from the lower part of the press shaft 28 through the heat resistant tube 37 at the center. Since it flows through the water channel 38 in the section to the upper outlet and is constantly cooled, there is no heat transfer from the heated section, and high accuracy can be maintained at all times.

However, the heat generated by the heater 39 of the molded receiving portion 25 is still transferred to the receiving base 41 through the heat insulating material 40. However, cooling water is injected into the lower part of the pedestal 41 from C, discharged upward from the nozzle 42, and flows to d, where it is constantly cooled, so that the transferred heat is blocked and the heat is transferred to the base 24. There isn't.

In such a configuration, the glass material 44 placed in the lower mold 43 is heated by the heater 39 and when it reaches a softening point, the upper mold 45 heated by the beater 35 is heated.
is lowered and molding is performed.

After molding, the heaters 39 and 36 are turned on while keeping pressure on the molded product.
must be cut and cooled until the hardening point is reached. In this embodiment, cooled N2 gas is injected into the molding press part 27 from e, and is rapidly cooled by discharging it from inside to outside through a plurality of small holes 48 provided in a heater block 47 through a heat-resistant tube 46. can do.

Similarly, the molded receiving part can be rapidly cooled by injecting cooled N2 gas from f and discharging it from the small hole 51 provided in the heater block 5o through the heat-resistant tube 49. q is an N2 gas intake port for creating an inert gas atmosphere inside the chamber. As described above, according to this embodiment, by including the forming heating part in the chamber and separately providing the lifting guide part for the press shaft outside the chamber, the lifting accuracy can be maintained.

In addition, the joint between the press shaft and the upper opening of the chamber is
Since it slides through a ring-shaped elastic body held by a flange made of heat insulating material, it not only has a sealing effect with the chamber, but also has extremely low heat conduction and is not in direct metal-to-metal contact with the chamber. Unfortunately, the thermal deformation of the chamber is not affected by the press shaft at all, and the accuracy of lifting and lowering can be ensured. In addition, heat conduction to the press shaft is prevented by flowing cooling water from the bottom end to the top end of the shaft core of the press shaft, and heat conduction to the base is also prevented by discharging cooling water from the bottom surface of the molded receiver. It is possible to prevent each thermal deformation from occurring.

Still, each heater pro for the molded push part and molded receiver part,
Multiple small holes are provided from the inside to the outside, and N2 is inserted from the inside.
By discharging gas, the heater block containing the heater can be rapidly cooled.

Effects of the Invention The present invention firstly provides a linear system in which a chamber includes a molding press part and a molding receiving part having a heating element, and a lifting guide for a press shaft connected to the molding press part is attached to an independent frame separate from the chamber. By using a bearing, the linear bearing part is not affected by the heating element, so that the vertical sliding accuracy of the press shaft can be maintained.

Second, because the sliding joint between the upper opening of the chamber and the press shaft slides through a ring-shaped elastic body held by a flange made of heat insulating material, heat transfer from the chamber is reduced. In addition to having a sealing effect, the atmosphere inside the chamber can be maintained. In addition, since there is no metal-to-metal contact on the press shaft, only the elastic body is in contact, the press shaft is not affected by the thermal deformation of the chamber itself, and the press shaft can still slide with high precision. can.

Thirdly, a cooling means through which water passes through the axial center of the press shaft and passes through both upper and lower ends, and a cooling means through which cooling water is discharged from a nozzle opening protruding from the lower end of the molding receiver. By providing this, it is possible to prevent heat conduction to the press shaft and the base surface, and to prevent thermal deformation from occurring in each.

Fourth, a plurality of small holes are provided in each of the heater blocks of the molding push part and the molding receiving part, penetrating from the inside to the outside from behind the heater, and the cooled N2 gas is discharged from the inside to the outside through these small holes. By doing so, the temperature of the molded product can be rapidly cooled while the pressure is maintained after molding, and the molding cycle time can be significantly shortened. In this embodiment, the sliding motion of the press shaft is only linear sliding, but depending on the purpose, a rotary actuator may also be used to provide rotation to the press shaft to obtain the same effect.

Further, in the non-embodiment, the frame supporting the linear bearing portion is fixed to the base, but it goes without saying that any frame that is separate from the chamber may be used. Although water is used as the cooling means in this embodiment, similar effects can be obtained using other media.

[Brief explanation of drawings]

FIG. 1 is a longitudinal cross-sectional view of a hot press molding machine according to an embodiment of the present invention, and FIG. 2 is an enlarged vertical cross-sectional view of a molding press processing section of the present invention.
FIG. 3 is a front view of a conventional hot press molding machine. 24...Base, 26...Chamber, 29
...Sliding, drive source (cylinder), 28...Press shaft, 27...Forming push part, 25...Forming receiving part, 33...Linear Bearing part, 32...
...Frame, 34...Ring-shaped elastic body (O
IJ tongue, 42... Protruding nozzle opening (nozzle), 43.45... Mold, 35° 39...
... Heater, 47.50 ... Heater block,
48.51 ...small hole. Name of agent: Patent attorney Toshio Nakao and one other person”−
-71>r; - 27-Ninbu Bajiyu 2 Figure 3

Claims (4)

[Claims] (1) A chamber fixed to the base and equipped with a heating means that includes the press-formed part, penetrating through the upper opening of this chamber and being able to slide up and down, and whose upper end is a sliding drive source. A press shaft connected to the press shaft, a molding push part fixed to a lower end of the press shaft inside the chamber, a molding receiving part fixed to a base in the lower part of the chamber and facing the molding push part, and the press shaft. It is composed of a linear bearing section that holds and guides sliding movement.
A hot press molding machine fixedly supported by a frame that is independently fixed so as to be separated from the chamber. (2) A chamber fixed on the base and equipped with a heating means that includes the press-formed part; a driving source that penetrates the upper opening of the chamber and is slidable up and down; the upper end is slidable; a press shaft connected to the press shaft; a molding pusher fixed to the lower end of the press shaft inside the chamber; a molding receiving part fixed to a base in the lower part of the chamber and facing the molding pusher; The linear bearing part holds the shaft and guides the sliding movement, and the linear bearing part is fixedly supported by an independently fixed frame separated from the chamber, and the A hot press molding machine comprising: a cooling means having a water passage formed substantially through the shaft core; a cooling means piped to allow water to flow through the water passage; and a cooling means for supplying cooling water to the lower end of the molding receiving part. (3) A chamber fixed to the base and equipped with a heating means that includes the press-formed part; a driving source that penetrates the upper opening of the chamber and is slidable up and down; the upper end is slidable; a press shaft connected to the press shaft; a molding pusher fixed to the lower end of the press shaft inside the chamber; a molding receiving part fixed to a base in the lower part of the chamber and facing the molding pusher; The linear bearing part holds the shaft and guides the sliding movement, and the linear bearing part is fixedly supported by a frame that is independently fixed so as to be separated from the chamber, and the molded push part A hot press molding machine in which both the molding receiving part and the molding receiving part respectively support opposing molds, and have a heating means in the vicinity of the mold and a cooling gas discharge port behind the heating means. (4) A chamber fixed on the base and equipped with a heating means that includes the press-formed part, penetrating through the upper opening of this chamber and being able to slide up and down, and whose upper end is a sliding drive source. A press shaft connected to the press shaft, a molding push part fixed to a lower end of the press shaft inside the chamber, a molding receiving part fixed to a base in the lower part of the chamber and facing the molding push part, and the press shaft. It is composed of a linear bearing section that holds and guides sliding movement.
They are fixedly supported by a frame that is independently fixed so as to be separated from the chamber, and both the molding push part and the molding receiving part respectively support opposing molds and apply heat to the vicinity of the molds. The sliding joint between the upper opening of the chamber and the press shaft passing through the opening is held by a flange made of a heat insulating material. A hot press molding machine equipped with a ring-shaped elastic body.