JPH0750182Y2 - 2-axis rotary hollow molding machine capable of measuring mold temperature - Google Patents

Description

[Detailed Description of the Invention] (Field of Industrial Application) This invention encloses a material resin in a mold that rotates (revolves and rotates) about two intersecting axes, and heats this mold in a furnace. The present invention relates to a biaxial rotation hollow molding machine for biaxially rotating and allowing a molten resin to flow evenly along the inner surface of a mold to mold a hollow body such as a container with resin.

(Prior Art) The two-axis rotary hollow molding method is used for molding relatively large containers such as a liquid tank.

As shown in FIG. 5, the outline of the structure is such that a part of the wall of the furnace 1 is a hollow rotating disk 2 and is rotated by a hollow revolution shaft 3. A lateral arm 4 is attached to the peripheral edge of the disk 2, and a die 6 is attached via a die support 11 to an upper part of a vertical rotation shaft 5 connected to the tip of the disc. At the center of the revolution shaft 3, there is a rotation drive shaft 7, which rotates a rotary shaft 9 provided in the lateral arm 4 via a transmission 8 (chain, gear, etc.) in the hollow rotating disc 2, Worm car,
The rotation shaft 5 is rotated via a transmission 10 such as a bevel gear. The mold support 11 is connected to the rotation shaft 5.

With this configuration, when the revolution shaft 3 and the rotation drive shaft 7 are rotated from outside the furnace, the mold 6 combines the revolution about the revolution shaft 3 and the revolution about the rotation shaft 5. Perform biaxial rotation.

When the material resin is enclosed in the mold 6 and the biaxial rotation is performed while heating in the furnace 1, the resin spreads over the entire inner surface of the mold as it melts, and the rotation speed ratio of the shafts 3 and 7 is appropriately selected. By doing so, the thickness of the molten resin layer on the inner surface of the mold can be made substantially uniform.

Depending on the container structure, there are those that want to have a two-layer structure for the vessel wall. Therefore, the first resin is first melted to mold the outer layer, and then the second resin is put into a mold and melted to form the inner layer. May be operated like molding. For that purpose, the second resin is put in the receiver 12 attached to the mold so as not to melt, and compressed air is sent to the actuator 13 after the outer layer is molded to open the valve to mold the second resin into the mold. In order to do so, a compressed air passage for driving the actuator, a cooling water passage for cooling the receiver, and a nitrogen gas passage for preventing resin oxidation are provided.

Explaining these passages with reference to FIGS. 5 to 7, there is a feed shaft 14 at the center of the rotation drive shaft 7, and as shown in FIG. 6, compressed air passages 15a and 15b and cooling water passages 16a and 16b. The nitrogen gas passages 17a and 17b are longitudinally provided, and the air pipes 19a and 19b and the water pipes are provided through the coupling 18 at the end of the feed shaft 14 outside the furnace.
20a, 20b and nitrogen pipes 21a, 21b are connected to the respective passages, and an air pipe, a water pipe, and a nitrogen pipe communicating with the passages are connected to a shaft end portion in the furnace via a coupling 22. This air pipe or the like is further connected to each passage in the rotation shaft 5 via a coupling 23 as shown in FIG. Compressed air is sent to the actuator 13 from the passage in the rotation shaft 5, the cooling water cools the receiver 12 to prevent the resin inside from being heated and melted, and the nitrogen gas is replaced with the air in the mold. It

(Problems to be Solved by the Invention) When performing biaxial rotation molding, it is important to operate while monitoring whether or not the temperature of the mold is suitable for the resin used.

However, heretofore, there has been no suitable method for measuring the temperature of a mold, which is hollow-molded while rotating, during operation.

As a possible measuring method in such a case, there is a method of projecting far-infrared rays and knowing the mold temperature from the intensity of the reflected light from the mold surface. Measurement is not possible because the distance to the surface fluctuates. It is also possible to extract the electric signal from the temperature sensor attached to the mold to the outside of the rotating shaft via the slip ring, but the weak signal current from the temperature sensor was extracted via the slip ring with large resistance. Then, the error becomes large and it is not practical.

Therefore, in the past, after performing an idle operation in which the mold was heated and rotated without inserting resin, the mold was taken out of the furnace, the mold temperature was measured, and the operating state of the furnace capable of melting the resin appropriately was estimated. However, in this method, since it takes time to remove the mold, the difference between the actual temperature of the furnace and the measured temperature becomes large. Further, as shown in FIG. 8, the temperature sensor 24 attached to the mold measures the temperature of a necessary portion, and this is rotated together with the mold in a furnace.
Although a device has been developed in which it is stored in 25 and is regenerated after the operation is finished to know the temperature condition, this method cannot be immediately controlled by knowing whether the mold temperature during operation is good or bad. Moreover, in the case of electrically measuring the temperature in this way, since the battery (dry cell) used as the power source has poor heat resistance, the above-mentioned measurement recorder includes a thick thermal insulation material for the entire recorder including the battery other than the sensor. Although it is placed in a heat-resistant box surrounded by to avoid being affected by heat, the usable time is as short as about 2 hours.

(Means for Solving the Problems) The present invention is to install a transmitter including a power supply battery and a transmitting antenna on a rotating shaft that rotates together with a mold, and wirelessly transmit a mold temperature signal detected by a sensor to a furnace. This signal is received by the receiving antenna provided, and this signal is sent to a receiver outside the furnace by a conductor so that the current mold temperature can be immediately known, and the part with the transmitter is cooled by cooling water. By enclosing the battery with a cover, the battery can be protected from the high temperature of the furnace, and the duration of measurement can be extended to solve the above problems.

(Function) The transmitter attached to the part that rotates with the mold is covered with a cooling cover that is kept at a low temperature through cooling water.
Even in a high-temperature furnace, the battery of the power source is not damaged, and the current mold temperature value can be transmitted for a long time.

(Embodiment) FIG. 1 shows an outline of the configuration of a two-axis rotary hollow molding machine of the present invention. The molding machine itself is the same as the conventional one shown in FIGS. 5 to 7, and the mold temperature is wirelessly transmitted. Only the part and its cooling structure are different. Therefore, the same parts as those in FIGS. 5 to 7 are designated by the same reference numerals, and the description thereof will be omitted.

A mounting plate 26 is fixed to the lower end of the rotation shaft 5 as shown in FIGS. 2 and 3, and a transmitter 27 and a temperature adapter are attached to the lower surface of the mounting plate 26.
A transmitter 41 including a battery 28 and a dry battery 29 is mounted. A cooling cover 30 is provided to cover the lower end of the rotation shaft.
In the example of FIG. 2, the cooling cover 30 is attached to the coupling 23. A cooling water passage 31 is provided in the cooling cover 30, and a part of water passing through the rotation shaft 5 is circulated through the coupling 23 to cool the cover 30. A transmitting antenna 32 is attached to the rotation shaft 5 below the mold support 11, and a receiving antenna 33 is attached to the inner surface of the furnace 1. It is more effective to provide not only one receiving antenna on the upper side but also a lower receiving antenna as the position of the die changes so that radio waves from the transmitting antenna can be received without being obstructed by the die. The receiving antenna 33 is connected to a receiver 34 outside the furnace by a conductor.

With the above configuration, the temperature sensor 24 is attached to the portion of the mold 6 where the temperature is desired to be known, and the conductor is attached to the temperature adapter
Connect to 28 and transmit temperature signal by transmitter 41 Antenna 32
It is possible to know the current temperature of the main part of the mold by transmitting the electric wave from the radio wave and transmitting it to the receiver 34 by capturing the electric wave with the receiving antenna 33.

This measurement is possible even during the operation in which the mold is revolving and rotating.

FIG. 4 shows a transmitting section when two receiving antennas 33 are provided,
The connection structure of a receiving part is shown. The temperature information obtained by the temperature sensor 24 is used as a signal current by the temperature adapter 28 in the cooling cover 30,
It is sent to the transmitting antenna 32 via the transmitting unit 27 and the matching device 35, and is emitted as a radio wave. This radio wave is received by the receiving antennas 33a, 3a.
3b, is guided by the lead wire to the receiver 34 outside the furnace, matching devices 36a, 36b, antenna combiner 37, receiver 38, demodulator 39
The temperature is displayed on the display unit 40 via.

Although the temperature inside the furnace 1 reaches a maximum of 450 ° C., the transmitter mounted on the mounting plate 26 is covered with the cooling water circulating portion of the coupling 23 and the cooling cover 30 cooled through the cooling water. The temperature can be kept at a temperature of not higher than 0 ° C, and a dry battery having low heat resistance can be sufficiently protected.

(Effects of the invention) (1) It is difficult in the conventional two-axis rotary hollow molding that the temperature information obtained by the temperature sensor can be known outside the furnace, and the mold performs a complicated motion combining the revolution and the rotation. You can immediately know the current temperature of the mold.

(2) Therefore, it is possible to quickly perform temperature control suitable for the resin used and obtain a good quality biaxial rotary hollow molded product.

(3) Since the transmitter is cooled by utilizing the cooling water supply structure for the mold, which has been provided in the past, it is not necessary to newly process the two-axis rotary molding machine.

[Brief description of drawings]

1 to 4 show an embodiment of the present invention, FIG. 1 is a side view of a two-axis rotary hollow molding machine showing the outline of the configuration, and FIG. , FIG. 3 is a bottom view of the transmitter mounting plate, FIG. 4 is a diagram showing the connection between the transmitter and the receiver, and FIGS. 5 to 8 show the outline of a conventional two-axis rotary hollow molding machine. Fig. 5 is a side view, and Fig. 6 is a fifth view showing the water supply channel, etc.
FIG. 7 is a sectional view taken along line AA in FIG. 7, and FIG. 7 is B in FIG.
-B sectional drawing and FIG. 8 are side views of the essential parts of the memory type temperature measuring device. 1: Furnace, 2: Rotating disk, 3: Revolution axis, 4: Lateral arm, 5: Rotation axis, 6: Mold, 7: Rotation drive axis, 8: Transmission, 9: Rotation axis, 10: Transmission , 1
1: Mold support, 12: Receiver, 13: Actuator, 14:
Feed shaft, 15a, 15b: compressed air passage, 16a, 16b: cooling water passage, 17a, 17b: nitrogen gas passage, 18: coupling, 19a, 1
9b: Air tube, 20a, 20b: Water tube, 21a, 21b: Nitrogen tube, 22, 23:
Coupling, 24: Temperature sensor, 25: Recorder, 26: Mounting plate, 27: Transmitter, 28: Temperature adapter, 29: Dry battery, 30: Cooling cover, 31: Cooling water passage, 32: Transmission antenna, 33: Reception antenna, 34: receiver, 35, 36a, 36b: matching device, 37: antenna combiner, 38: reception unit, 39: temperature demodulation unit, 40: display unit, 41:
Transmitter.

Claims (1)

[Scope of utility model registration request] 1. A temperature sensor attached to a mold in a part that rotates together with the mold (6) in a two-axis rotary hollow molding machine in which the mold is rotated about the revolution axis and the rotation axis in the furnace. A transmitter (41) and a transmitting antenna (32) for wirelessly transmitting the temperature signal obtained by (24) are provided, and the transmitter (41) including the battery (29) is cooled by providing a cooling water passage. Cover with cooling cover (30) and receive antenna (33) in furnace (1)
A two-axis rotary hollow molding machine capable of measuring the mold temperature, which is equipped with a receiver (34) that is attached to the outside of the furnace to demodulate the radio signal captured by the receiving antenna to obtain temperature information.