JP3641641B2 - Mold temperature control system in molding equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a mold temperature control system in a molding apparatus provided with a heating mechanism for heating a molded product during molding of synthetic resin or the like.
[0002]
[Prior art]
Some synthetic resin molding apparatuses such as stamping molding, injection molding, slush molding, and blow molding have a heating mechanism provided in a mold in order to perform desired molding. For example, FIG. 7 and FIG. 8 show an example of a molding apparatus in the case where a laminated body in which the base material 5 is covered with the composite layer 6 composed of the skin layer 7 and the foam layer 8 is manufactured by stamping molding. The mold 3 is provided with temperature control pipes 2 and 4 through which hot water and cold water for heating and cooling pass. First, as shown in FIG. 7, the base material 5 is set on the upper surface 1a of the lower mold 1, and consists of a front side molten resin layer 7m extruded from the supply die 9 into a sheet shape and an inner side molten resin layer 8m mixed with a foaming agent. The upper surface of the base material 5 is covered with the molten resin laminate 6m, and the upper mold 3 is approached and stopped so that a slight gap is left between the molten resin laminate 6m and the front-side molten resin layer 7m. Then, both molds 1 and 2 are heated by passing warm water through the temperature control pipes 2 and 4, and the inner molten resin layer 8m is foamed as shown in FIG. 8, so that the molten resin laminate 6m is placed between the substrate 5 and the upper mold 3a. The composite layer 6 in which the molten resin laminate 6m is cooled and cured by passing cold water through the temperature control pipes 2 and 4 and then the upper mold 3 is raised, and the laminate in which the base material 5 is covered with the composite layer 6 is obtained. I try to take it out.
[0003]
For example, as shown in Japanese Patent Application Laid-Open No. 62-122086, an eddy current is induced in a mold made of a high resistance material such as iron or nickel by an induction coil, and the mold is heated by Joule heat of the eddy current. There is also a technique like this.
[0004]
[Problems to be solved by the invention]
In the first prior art described above, heating with warm water has little variation in temperature distribution and good temperature stability, but since warm water used for heating is usually 100 ° C. or less, it can only be heated below that, There is a problem that the heating rate cannot be increased because of heating by transmission. On the other hand, if high-temperature water whose boiling temperature is set to 100 ° C. or higher by pressurization is circulated through the temperature control piping of each mold, similarly good temperature stability can be obtained. Although it is possible to heat to 100 ° C. or higher at a high temperature rise rate, the temperature rise rate cannot be increased so much because it is still heating by heat transfer.
[0005]
In addition, in order to produce a product with partially different characteristics, for example, a product having a partially increased foaming ratio in the production of a laminate having a foamed layer as described above, that part of the mold is replaced with another part. It is necessary to heat faster or stronger than the part to promote foaming, and in that case, heating by an induction coil is suitable as in the second prior art described above. However, the heating by the induction coil tends to cause a variation in temperature distribution, which may cause a problem that the characteristics vary, such as non-uniform foaming.
[0006]
The present invention includes heating with a heat medium from a heating medium supply device such as a pressurized water supply device and a hot water supply device, and cooling with a heat medium from a cooling medium supply device such as a chiller water supply device and a tower water supply device, It aims at solving each problem as mentioned above by combining the heating by an induction heating coil appropriately.
[0007]
[Means for Solving the Problems]
The mold temperature control system in the molding apparatus according to the present invention has a pair of molds in which molding surfaces are formed on the surfaces facing each other. A temperature control pipe for heating and cooling the vicinity of the molding surface of the mold by circulating a heat medium such as hot water or cold water provided in at least one of both molds, Heated heating medium A hot water supply device and a pressurized water supply device for supplying hot water and pressurized hot water respectively. An electromagnetic valve comprising a heating medium supply device, a cooling medium supply device for supplying a cooled heat medium, and a plurality of electromagnetic valves for supplying the heating medium from the heating medium supply device and the cooling medium supply device to a temperature control pipe. An assembly, an induction heating coil provided in a molding die provided with temperature control piping and heating a part of the molding surface of the molding die, a molding device, a solenoid valve assembly, and induction heating based on a predetermined procedure A control device for controlling the operation of the coil is provided. According to the present invention, the molding surface of the mold is Two types of hot water from the pressurized water supply device and hot water from the hot water supply device While being heated by the heat medium without variation in temperature distribution, the portion provided with the induction heating coil is partially and strongly heated quickly. Further, after molding, it is cooled by cold water from a cooling medium supply device.
[0008]
It is preferable that the temperature control pipe provided in at least one of the two molds is divided into a plurality of portions. In this way, only a part of the molding surface of the mold can be heated and cooled by the heat medium.
[0010]
The cooling medium supply device is a chiller water supply device that supplies chilled water cooled using a refrigerant. as well as It is good also as what consists of a tower water supply apparatus which supplies the tower water cooled by the air cooling.
[0011]
Prior to the operation of the induction heating coil, the aforementioned control device is preferably one that switches and operates the electromagnetic valve assembly so as to circulate and supply high temperature water from the pressurized water supply device to the temperature control pipe. In this way, the portion provided with the induction heating coil is first preheated with high-temperature water and then quickly heated by the induction heating coil.
[0012]
In addition, the controller switches the solenoid valve assembly to circulate and supply chiller water from the chiller water supply device to the temperature control piping after stopping the circulation supply of high temperature water from the pressurized water supply device to the temperature control piping. It is good also as what makes it. If it does in this way, the cooling rate in the case of cooling the shape | molded product will become large.
[0013]
Further, the control device stops the supply of the chiller water in the middle of the temperature drop of the mold due to the supply of the chiller water from the chiller water supply device, and circulates and supplies the hot water from the hot water supply device to the temperature control pipe. The electromagnetic valve assembly may be switched and operated. In this way, the mold is not overcooled by chiller water.
[0014]
A pressurized water circulation pipe having a bypass electromagnetic valve is connected to the pressurized water supply apparatus, a hot water circulation pipe having a bypass electromagnetic valve is connected to the hot water supply apparatus, and a chiller water circulation pipe having a bypass electromagnetic valve is connected to the chiller water supply apparatus. The temperature control pipe is connected to each circulation pipe at a position on both sides of the bypass solenoid valve via the forward pipe and the return pipe each provided with a solenoid valve assembly, and the control device is connected to each circulation pipe. In a state where the passage is not connected to any of the temperature control pipes, it is preferable to open a bypass solenoid valve provided in the circulation pipe. In this way, the heat medium is circulated through the circulation pipe even when each circulation pipe is not in communication with any of the temperature control pipes, so that the temperature of the heat medium is kept stable. It is.
[0015]
Preferably, the pressurized water supply device can adjust the temperature of the pressurized hot water, and the induction heating coil can adjust the output.
[0016]
At least one temperature sensor for detecting the temperature of at least one of the molds is provided, and the control device supplies the hot water and outputs the induction heating coil based on the temperature detected by the temperature sensor and a predetermined procedure. Is preferably controlled.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
1 to 6, an embodiment in which the mold temperature control system in a molding apparatus according to the present invention is applied to a molding apparatus for an automobile door trim will be described.
1 to 3 show cross-sectional views of the molding apparatus in each operating state. The door trim manufactured according to the present invention has a composite layer 31 composed of a skin layer 32 and a foamed layer 33 on the surface of a rigid base material 30 that has been molded in advance, as shown in FIG. It is a covered laminate. The base material 30 is a porous material having air permeability, and is hot-press-molded into a plate having an irregularity with a roughly constant thickness by mixing about 7% phenol resin as a binder into finely crushed fibers of wood. Is. The composite layer 31 is formed by integrally superimposing a skin layer 32 on the front surface side and a foam layer 33 on the base material 30 side, and an upper half portion (left half portion in the figure) of the door trim and an armrest portion subsequent thereto. Increases the thickness of the foamed layer 33 and increases the foaming ratio so that a softer feel than other parts can be obtained.
[0018]
The molding apparatus used in this embodiment is attached to a first molding die (lower die) 10 that is attached to a lower fixed-side support member (not shown) and an upper movable-side support member (not shown). And a supply die 35 for extruding and supplying a molten resin laminate 31m that is a material of the composite layer 31. Yes. Forming surfaces 10a and 20a are formed on the opposing surfaces of the forming dies 10 and 20, respectively.
[0019]
As shown in FIGS. 1-3, the 1st shaping | molding surface 10a of the 1st shaping | molding die 10 upper surface supports the back surface of the base material 30 shape | molded previously as mentioned above, and along the outer periphery, it is. An outward stepped portion 10b whose planar contour shape matches the contour shape of the door trim is formed. In this embodiment, the first molding die 10 is made of a low resistance material such as an aluminum casting, and the back side opposite to the first molding surface 10a is largely cut out and reinforced by a plurality of ribs 10c. ing. A temperature control pipe 13 made of a stainless steel pipe or the like and divided into a plurality of portions as described later is cast into the first mold 10 along the inner side of the first molding surface 10a.
[0020]
A portion of the first mold 10 between the upper half of the door trim and a part of the temperature control pipe 13 corresponding to the armrest portion is removed from the back side, and is a thick plate made of a high resistance material such as iron. The plurality of blocks 15 are closely attached and fixed. The surface on which the block 15 is embedded is substantially parallel to the first molding surface 10 a of the first mold 10, and the induction heating coil 16 is fixed to the surface on the outside of each block 15. The induction heating coil 16 is formed by stacking a plurality of flat coils wound in a spiral shape and connecting them in series. The first mold 10 is attached to the fixed-side mold support member via the surface plate 19.
[0021]
Similarly, as shown in FIGS. 1 to 3, the second molding die 20 is a surface layer 21 in which a second molding surface 20 a that forms the surface of the composite layer 31 that is molded by nickel electroforming and covers the door trim is formed on the lower surface. The outer frame 22a and the plurality of reinforcing ribs 22 forming the frame 22 are fixed to the surface layer 21 by welding. The inwardly stepped portion 20b formed on the surface layer 21 along the outer periphery of the second molding surface 20a has a slight amount in the state where both molds 10 and 20 are in the closest position as shown in FIGS. It can be fitted to the outward stepped portion 10b of the lower mold 10 with a gap. The temperature control pipe 23 made of a stainless steel pipe or the like and divided into a plurality of portions as described later is welded and fixed along the back surface (upper side) of the surface layer 21 before the frame 22 is welded.
[0022]
In addition, an induction heating coil 26 is tightly fixed to the back surface of the surface layer 21 between the temperature control pipes 23 corresponding to the upper half of the door trim and the armrest portion. Each induction heating coil 26 has substantially the same structure as that provided in the first mold 10, but a part of the induction heating coil 26 is bent in accordance with the back surface shape of the surface layer 21. The second molding die 20 is attached to the movable side mold support member via the surface plate 29. The back surface of the surface layer 21 between the frame 22, the temperature control pipe 23 and the induction heating coil 26 is backed and reinforced by a backing 24 made of an epoxy resin mixed with aluminum powder.
[0023]
As shown mainly in FIGS. 2 and 3, in a state where both molds 10 and 20 are in the closest position, the surface 30a of the substrate 30 supported by the first molding surface 10a of the first mold 10 and the first The space | interval between the 2nd shaping | molding surfaces 20a of the 2 shaping | molding die 20 is large in the upper half part and subsequent armrest part (especially the upper part) of a door trim, and is small in the lower half part. The blocks 15 and the induction heating coils 16 and 26 provided in the respective molds 10 and 20 are provided corresponding to the portions where the distance is large. In addition, this space | interval of the part corresponded to this lower half part is a little larger than the molten resin laminated body 31m mentioned later.
[0024]
In the molding apparatus of this embodiment, as shown in FIG. 1, in a state where the second mold 20 is spaced upward, a supply die 35 that protrudes and moves above the first mold 10 that supports the base material 30. In addition, two supply pipes 36 (FIG. 1 shows only one) for supplying a synthetic resin material in a molten state to be the skin layer 32 and the foam layer 33 are provided. The material of the skin layer 32 and the foam layer 33 to be the composite layer 31 is a polyolefin-based synthetic resin (for example, polypropylene), and a foaming agent (for example, an azodicarbonamide-based material) is kneaded in the material of the foam layer 33. Has been.
[0025]
An alternating current (1 kilohertz or less) applied to the induction heating coil 26 of the second mold 20 from a transistor inverter (not shown) induces an eddy current in the surface layer 21 near the induction heating coil 26 by electromagnetic induction, and this eddy current. The surface layer 21 of the magnetic high-resistance element generates heat due to Joule heat, and the second molding surface 20a of the second molding die 20 in the vicinity where the induction heating coil 26 is provided is heated. The temperature of the second molding surface 20a can be adjusted by adjusting the transistor inverter to change the output state of the induction heating coil 26 such as the output and timing. Similarly, if an alternating current is applied to the induction heating coil 16 of the first mold 10, an eddy current is induced in the block 15 by electromagnetic induction, whereby the magnetic high resistance block 15 generates heat and the temperature rises. The vicinity of the mold 10 in close contact with the mold 15 is heated by heat conduction from the block 15, and the first molding surface 10 a of the first mold 10 in the vicinity where the induction heating coil 16 is provided can be heated. . However, in this embodiment, heating by the induction heating coil 16 of the first mold 10 is not performed.
[0026]
Next, referring to FIGS. 4 and 5, the temperature control pipes 13 and 23 provided in the respective molds 10 and 20 and the structure for supplying a heat medium such as water heated or cooled to the temperature control pipes will be described. As described above, the temperature control pipe 13 provided in the first mold 10 that is not heated by the induction heating coil 16 has four general pipes 13b1, 13b2, 13b3, 13b4 and two, as shown in FIG. The peripheral pipes 13b1, 13b2, 13b3, 13b4 are provided at positions corresponding to the entire surface except for the peripheral part of the door trim, and the peripheral pipes 13c1, 13c2 are arranged around the door trim. It is provided at a position corresponding to the part. On the other hand, as shown in FIG. 5, the temperature adjusting pipe 23 provided in the second mold 20 for heating by the induction heating coil 26 includes two high-foaming part pipes 23a1, 23a2, and general part pipes 23b1, 23b2. And the high-foam part pipes 23a1 and 23a2 are provided at positions corresponding to the induction heating coil 26, that is, positions corresponding to the upper half of the door trim and the armrest part. 23b1 and 23b2 are provided at positions corresponding to the lower half of the door trim, and peripheral pipes 23c1 and 23c2 are provided at positions corresponding to the peripheral part of the door trim.
[0027]
As shown in FIGS. 4 and 5, the mold temperature control system according to the present invention includes a pressurized water supply device 40 that supplies pressurized high-temperature water (for example, 160 ° C.), and hot water that supplies normal warm water (for example, 50 ° C.). A supply device 41, a chiller water supply device 42 for supplying chiller water (for example, 10 ° C.) strongly cooled using a refrigerant, and a tower water supply device for supplying tower water (for example, 25 ° C.) cooled by an air-cooled cooling tower 43. Each supply device 40, 41, 42, 43 supplies high-temperature water, hot water, chiller water, and tower water to both the first mold 10 and the second mold 20. Hot water, hot water, chiller water, and tower water can all be temperature-adjusted, and in particular, high-temperature water can be temperature-controlled in a considerable range.
[0028]
First, referring to FIG. 5, the heated or cooled water or the like from each of the supply devices 40, 41, 42, 43 with respect to the temperature control pipe 23 of the second mold (upper mold) 20 including the high foaming section pipes 23a1, 23a2. The heating medium supply path will be described. Each tip of the pressurized water circulation pipe 40a2 divided into the supply side and the return side by the bypass solenoid valve V29p is connected to the supply port and the return port of the pressurized water supply device 40, respectively, and divided into the supply side and the return side by the bypass solenoid valve V29h. Each tip of the hot water circulation pipe 41a2 is connected to a supply port and a return port of the hot water supply device 41, respectively, and each tip of the chiller water circulation pipe 42a2 divided into a supply side and a return side by a bypass solenoid valve V29c. The chiller water supply device 42 is connected to the supply port and the return port.
[0029]
The forward line 45a2 and the return line 45b2 connected to the inlet side and the outlet side of the high foaming portion pipes 23a1 and 23a2 are connected to the supply side and the return side of the pressurized water circulation line 40a2 through the electromagnetic valves V21p and V22p. The hot water circulation line 41a2 is connected to the supply side and the return side via the electromagnetic valves V21h and V22h, and is connected to the supply side and the return side of the chiller water circulation line 42a2 via the electromagnetic valves V21c and V22c. The forward line 46a2 and the return line 46b2 connected to the inlet side and the outlet side of the general pipes 23b1 and 23b2 are also connected to the supply side and the return side of the pressurized water circulation line 40a2 via the electromagnetic valves V23p and V24p. It is connected to the supply side and the return side of the hot water circulation line 41a2 via the electromagnetic valves V23h and V24h, and is connected to the supply side and the return side of the chiller water circulation line 42a2 via the electromagnetic valves V23c and V24c. The forward pipe 47a2 and the return pipe 47b2 connected to the inlet side and the outlet side of the peripheral pipes 23c1 and 23c2 are connected to the supply port and the return port of the tower water supply device 43 through electromagnetic valves V25t and V26t. .
[0030]
Solenoid valves V21p, V21h, V21c, V22p, V22h, V22c, V23p, V23h, V23c, V24p, V24h, V24c, V25t, V26t constitute the second solenoid valve assembly V2 and are detected by temperature sensors T21, T22, T23 Opening / closing control is performed by the control device 50 based on the set temperature and a predetermined sequence. As a result, the high-temperature water, hot water, and chiller water from each supply device 40, 41, 42 are divided into temperature control pipes so that the temperature of the molding surface 20a of the second mold 20 changes as described later. 23a1, 23a2, 23b1, 23b2 are switched and supplied. Each bypass solenoid valve V29p, V29h, V29c is in a state where the circulation pipes 40a2, 41a2, 42a2 provided with the bypass solenoid valves V29p, V29h, V29c are not communicated with any of the high foaming pipes 23a1, 23a2 and the general pipes 23b1, 23b2. Then, it is opened and controlled by the control device 50 so as to circulate hot water, hot water or chiller water through the circulation pipes 40a2, 41a2, and 42a2. In this embodiment, the solenoid valves V25t and V26t are always open, and the tower water from the tower water supply device 43 is always supplied to the peripheral pipes 23c1 and 23c2.
[0031]
Next, with reference to FIG. 4, the supply path of the heating medium such as heated or cooled water from each of the supply devices 40, 41, 42, 43 to the temperature control pipe 13 of the first mold (lower mold) 10 will be described. To do. As in the case of the second mold 20, each tip of the pressurized water circulation pipe 40a1 divided into two by the bypass solenoid valve V19p is connected to the pressurized water supply device 40 and divided into two by the bypass solenoid valve V19h. Each tip of the hot water circulation pipe 41a1 is connected to the hot water supply device 41, and each tip of the chiller water circulation pipe 42a1 divided into two by the bypass electromagnetic valve V19c is connected to the chiller water supply device 42.
[0032]
The forward pipe 46a1 and the return pipe 46b1 connected to the inlet side and the outlet side of the general pipes 13b1, 13b2, 13b3, and 13b4 are connected to the supply side and the return side of the pressurized water circulation pipe 40a1 through the electromagnetic valves V13p and V14p. Connected to the supply side and the return side of the hot water circulation pipe 41a1 through the solenoid valves V13h and V14h, and connected to the supply side and the return side of the chiller water circulation pipe 42a1 through the solenoid valves V13c and V14c. ing. The forward pipe 47a1 and the return pipe 47b1 connected to the inlet side and the outlet side of the peripheral pipes 13c1 and 13c2 are connected to the supply port and the return port of the tower water supply device 43 through electromagnetic valves V15t and V16t. .
[0033]
The solenoid valves V13p, V13h, V13c, V14p, V14h, V14c, V15t, and V16t constitute a first solenoid valve assembly V1, based on the temperature detected by the temperature sensors T11, T12, T13 and a predetermined sequence. Opening and closing is controlled by the control device 50. Accordingly, the high-temperature water, the hot water, and the chiller water from the supply devices 40, 41, and 42 are divided into the general pipes 13b1 so that the temperature of the molding surface 10a of the first molding die 10 changes as described later. , 13b2, 13b3, 13b4. The bypass solenoid valves V19p, V19h, V19c are opened when the circulation pipes 40a1, 41a1, 42a1 provided with the bypass solenoid valves V19p, V19h, V19c are not communicated with any of the general pipes 13b1, 13b2, 13b3, 13b4. It is controlled by the control device 50. In this embodiment, the solenoid valves V15t and V16t are always open, and the tower water from the tower water supply device 43 is always supplied to the peripheral pipes 13c1 and 13c2.
[0034]
On the back surface of the surface layer 21 of the second mold 20, temperature sensors T21, T22 are provided corresponding to the portions provided with the high-foaming portion piping 23a1, 23a2, the general portion piping 23b1, 23b2, and the peripheral portion piping 23c1, 23c2, respectively. , T23 are provided. In the first mold 10, temperature sensors T11, T12, T13 are provided at positions corresponding to the temperature sensors T21, T22, T23 and close to the first molding surface 10a. The temperatures detected by the temperature sensors T11, T12, T13, T21, T22, T23 are input to the controller 50.
[0035]
Next, the change characteristic of the mold temperature of the molding apparatus of this embodiment will be described with reference to FIG. The molding apparatus is turned on, and the temperature of each molding surface 10a, 20a of both molds 10, 20 is set to temperature H1 (for example, 50 ° C.) by the warm-up procedure (not shown), and the second mold 20 is separated upward. In this state, the operation switch is turned on after setting the preformed base material 30 on the first molding surface 10a (time T0).
[0036]
First, the temperature of the first molding surface 10 a of the first mold 10 is changed as indicated by the characteristic line A. That is, the temperature first rises as shown by line A1 and reaches temperature H2 at time T2, and is maintained at temperature H2 as shown by line A2 until time T5, and from time T5 to time T6 as shown by line A3. It decreases rapidly to H1. The temperature H1 is maintained as indicated by line C until the next molding cycle starts. The control device 50 controls the first electromagnetic valve assembly V1 based on a predetermined sequence so that the general pipes 13b1, 13b2, 13b3, and 13b4 of the first mold 10 are heated and the temperature H2 is increased. When the temperature is kept low, the pressurized high-temperature water is mainly supplied from the pressurized water supply device 40, and when the temperature after the supply of the high-temperature water is suddenly lowered, the high-temperature water is mainly supplied from the chiller water supply device 42. Chiller water is supplied, and hot water from the hot water supply device 41 is mainly supplied when the temperature is maintained at the temperature H1. The switching between the supply of chiller water from the chiller water supply device 42 and the supply of hot water from the hot water supply device 41 is performed in the middle of the temperature drop of the first molding surface 10a earlier than the time point T6, and the first molding surface 10a due to overshoot. This prevents excessive cooling of the product. The time intervals between the time points T0 and T2, the time points T2 and T5, and the time points T5 and T6 are, for example, about 50 seconds, 100 seconds, and 30 seconds, respectively. The temperature H2 is 130 ° C., for example.
[0037]
Next, the temperature of the second molding surface 20 a of the second mold 20 is changed as indicated by the characteristic line B. This characteristic line B is a combination of lines B1, B2, and B4 in the portion corresponding to the lower half of the door trim, and lines B1, B3, B2, and B4 in the portion corresponding to the upper half of the door trim and the armrest portion. It is a combination. As in the case of the first mold 10, the control device 50 controls the second electromagnetic valve assembly V <b> 2 based on a predetermined sequence so that the high foam portion pipes 23 a 1 and 23 a 2 of the second mold 20 and the general part are controlled. When the temperature rises and is maintained at the temperature H2, the pressurized high-temperature water is mainly supplied from the pressurized water supply device 40 to the pipes 23b1 and 23b2, and the temperature after the supply of the high-temperature water is stopped suddenly. When the temperature drops, the chiller water is mainly supplied from the chiller water supply device 42. When the temperature is kept at the temperature H1, the hot water is mainly supplied from the hot water supply device 41. An alternating current from the transistor inverter is applied to the induction heating coil 26 between T1 and time T3. As in the case of the first mold 10, in order to prevent the second molding surface 20a from being overcooled due to overshoot, the supply of chiller water and hot water is switched in the middle of a temperature drop earlier than the time point T6.
[0038]
As a result, the temperature of the second molding surface 20a first rises more quickly than the line A1, as shown by the line B1, and reaches the temperature H3 at a time T4 later than the time T2 in the portion corresponding to the lower half of the door trim. Until the time T5, the temperature is maintained at the temperature H3 as indicated by the line B2, and from the time T5 to the time T6, the temperature rapidly decreases to the temperature H1 as indicated by the line B4, and is indicated by the line C until the start of the next molding cycle. The temperature is kept at H1. Further, in the portion corresponding to the upper half of the door trim and the armrest portion, it rises along line B1 until time T1, which is earlier than time T2, and then rises along line B3 until time T3 between time T2 and time T4. The temperature reaches the temperature H3 and is maintained at the temperature H3 as shown by the line B2 until the time T5, and rapidly decreases to the temperature H1 as shown by the line B4 from the time T5 to the time T6 until the next molding cycle starts. The temperature is kept at H1. The time intervals between time points T0 and T1, time points T1 and T3, time points T3 and T5, and time points T5 and T6 are, for example, about 25 seconds, 35 seconds, 90 seconds, and 30 seconds, respectively.
[0039]
In the vicinity of time T2 when the temperatures of the molding surfaces 10a and 20a are rising, the control device 50 starts the supply of the molten resin laminate 31m by the supply die 35. The materials of the melted skin layer 32 and the foamed layer 33 supplied from the extruder for measuring and extruding the resin to the supply die 35 through the supply pipe 36 are joined to each other and integrally laminated. Further, it is a two-layer sheet-like molten resin laminate 31m rich in plastic, comprising a front side molten resin layer 32m (temperature is about 160 ° C.) and an unfoamed inner molten resin layer 33m (temperature is about 110 ° C.). The extrusion die 35a is extruded from an elongated slit-like extrusion port 35a. At the same time, the supply die 35 moves rightward in FIG. 1, and the molten resin laminate 31m faces the upper side of the first mold 10 and the base material 30 set thereon with the inner molten resin layer 33m side down. Supplied to cover the entire ridge.
[0040]
After confirming that the molten resin laminate 31m is supplied and the supply die 35 has been retracted from above the first mold 10 with a limit switch or the like, the control device 50 points the second mold 20 toward the first mold 10. The second mold 20 is stopped from descending when the closest state shown in FIG. 2 is reached. In this clamped state, the space between the surface 30a of the base material 30 supported by the first mold 10 and the second molding surface 20a of the second mold 20 is a portion that becomes the upper half of the door trim and the armrest part. Is larger than the lower half, and the distance between the latter is greater than the thickness of the unfoamed molten resin laminate 31m. In the middle of this clamping, the unnecessary portion of the molten resin laminate 31m that protrudes outward from the outward stepped portion 10b of the first mold 10 is cut off by the shearing action of the two stepped portions 10b and 20b that fit together. . The outward and inward stepped portions 10b and 20 used for cutting away unnecessary portions of the molten resin laminate 31m have an inward stepped portion on the first molding die 10 side and an outward stepped portion on the second molding die 20 side. It is good. Alternatively, instead of shearing by such stepped portions, a pressing blade provided downward along the outside of the second molding surface 20a of the second molding die 20 is formed on the flat portion of the outer periphery of the first molding die 10. You may make it carry out by pressing. This mold clamping ends near time T4.
[0041]
The controller 50 maintains the mold clamping state from the vicinity of the time T4 when the mold clamping is completed to the time T6, and the inner molten resin layer 33m is second molded through the thin front side molten resin layer 32m slightly before the time T4. It is heated by the second molding surface 20a of the mold 20 to start foaming. The temperature of the second molding surface 20a at the initial stage of foaming is such that the portion provided with the high foaming portion pipes 23a1, 23a2 and the induction heating coil 26 reaches the temperature H3 earlier than the other portions. The upper half portion of the door trim and the armrest portion (particularly the upper half portion) having a large distance between the surface 30a of the base material 30 and the second molding surface 20a of the second mold 20 are the lower half of the door trim. The inner molten resin layer 33m is promoted to be foamed by being heated faster and stronger than the portion to be the portion. Accordingly, the portion with the large interval is foamed more rapidly than the portion corresponding to the lower half of the door trim with the small interval, and is filled at a large expansion ratio.
[0042]
The temperatures of the molding surfaces 10a and 20a of both molds 10 and 20 begin to decrease when reaching the time point T5, decrease to the temperature H1 at the time point T6, and thereafter maintain the temperature H1. Before and after this time T6, the control device 50 raises the second mold 20 to open the mold, removes the molded door trim from the first mold 10, and ends the operation of one cycle. . This returns to the same state as the completion of the warm-up described at the beginning of the description of the operation. If the preform 30 is set on the first molding surface 10a and the operation switch is turned on, the molding cycle of the next door trim is completed. Be started.
[0043]
In the door trim obtained as described above, the foaming layer 33 has a large foaming ratio in the upper half part and the armrest part (particularly the upper half part), so that a sufficient soft feeling can be obtained, and in the lower half part, the foam layer 33 Since the expansion ratio is small, sufficient durability can be obtained.
[0044]
The temperature of the molding surfaces 10a and 20a of the molds 10 and 20 when the inner molten resin layer 33m is foamed can be adjusted by changing the supply state such as the temperature of high-temperature water and the supply timing by the control device 50. . In particular, the temperature of the portion where the induction heating coil 26 of the second molding surface 20a is provided is adjusted separately from the other portions by changing the output state of the induction heating coil 26 and the timing by the control device 50. Can do. Thereby, the change range of the characteristic of the product which can be manufactured by a single process can be expanded.
[0045]
Further, in the above embodiment, the temperature of each molding surface 10a, 20a of each mold 10, 20 is detected by each temperature sensor T11, T12, T13, T21, T22, T23, and this temperature is as shown in FIG. The control device 50 adjusts the output state of the induction heating coil 26 such as the output and timing, the temperature of the high-temperature water from the pressurized water supply device 40, and the supply state such as the opening and closing timings of both solenoid valve assemblies V1 and V2 so as to change. doing. Thereby, the accuracy of temperature control of each molding surface 10a, 20a is raised.
[0046]
In the embodiment described above, the molding surfaces 10 a and 20 a of the molds 10 and 20 are heated by different heating means such as high-temperature water from the pressurized water supply device 40, hot water from the hot water supply device 41, and the induction heating coil 26. Therefore, as a whole, the portion that is stably heated and is provided with the induction heating coil 26 can be heated quickly and partially with a small variation in temperature distribution. In this way, it is possible to change the temperature in part by quickly and strongly heating the molding surface, so that products with partially different characteristics can be manufactured in a single process, and the temperature distribution varies. Therefore, stable characteristics can be obtained for each part. Further, the portion with a high foaming ratio that tends to be long in heating time can be quickly heated by the induction heating coil 26 in addition to the high-temperature water from the pressurized water supply device 40, and after molding, the chiller water from the chiller water supply device 42. Therefore, it is possible to quickly cool down, thereby shortening the molding cycle and increasing the production efficiency.
[0047]
The first molding surface 10a of the first mold 10 corresponding to the upper half of the door trim and the arm rest (particularly the upper half) that needs to be heated quickly and strongly is prior to the induction heating coil 26 being operated. Since high temperature water from the pressurized water supply device 40 is circulated and supplied to the high foaming portion pipes 23a1 and 23a2 and then heated prematurely by the induction heating coil 26, the variation in temperature distribution becomes relatively small and the temperature rises. Speed will also increase.
[0048]
In addition, the general pipes 13b1, 13b2, 13b3, 13b4, the high-foaming pipes 23a1, 23a2, and the general pipes 23b1, 23b2 are circulated with chiller water after the supply of high-temperature water from the pressurized water supply device 40 is stopped. Since it supplies, the cooling rate of the molded product is increased and the molding cycle can be further shortened.
[0049]
Also, the switching of the supply of chiller water from the chiller water supply device 42 and hot water from the hot water supply device 41 to the general pipes 13b1, 13b2, 13b3, 13b4, the high foaming pipes 23a1, 23a2, and the general pipes 23b1, 23b2 is timed. Since the process is performed in the middle of the temperature drop earlier than T6, the first molding surface 10a is not excessively cooled by overshoot, and the heating time in the next process can be shortened to further shorten the molding cycle.
[0050]
The pressurized water supply device 40, the hot water supply device 41, and the chiller water supply device 42 are connected to the pressurized water circulation pipes 40a1, 40a2, the hot water circulation pipes 41a1, 41a2, and the chiller water circulation pipes 42a1, 42a2, respectively, each having a bypass electromagnetic valve. In the state where each circulation pipe is not connected to any one of the general pipes 13b1, 13b2, 13b3, 13b4, the high foaming pipes 23a1, 23a2, and the general pipes 23b1, 23b2, a bypass provided in the circulation pipe The solenoid valve is opened. Therefore, even when each circulation pipe is not connected to any of the pipes, high-temperature water, hot water, or chiller water is circulated to keep the temperature of these heat media stable. As a result, a heat medium having a predetermined temperature is supplied to each pipe from the beginning in accordance with the switching operation of the electromagnetic valve, so that there is no delay in raising and lowering the temperature of each molding surface 10a, 20a.
[0051]
In the above embodiment, the molding surface 20a of the second mold 20 is divided into two parts, the part corresponding to the upper half of the door trim and the armrest part, and the other part, and the temperature is changed. The present invention can also be implemented by dividing the second molding surface 20a into three or more parts and changing the temperature of each part. In this case, two or more pressurized water supply devices 40 that supply high-temperature water having different temperatures and two or more sets of induction heating coils 26 having different outputs may be used.
[0052]
In the above embodiment, only the induction heating coil 26 provided in the second mold 20 is operated, but the present invention is also implemented by operating the induction heating coil 16 provided in the first mold 10. Also good.
[0053]
Further, in the above embodiment, the preformed base material 30 is used. However, in the present invention, the molten resin laminated body 31m extruded and supplied from the supply die 35 is made into three layers including the molten resin layer to be the base material 30. The preformed base material can be omitted.
[0054]
When the present invention is applied to injection molding or blow molding, the first molding die 10 and the second molding die 20 can be arranged horizontally instead of being vertically arranged as described above.
[0055]
【The invention's effect】
According to the present invention described above, the heating medium supply device In addition to a hot water supply device and a pressurized water supply device. Induction heating coil with different characteristics The Combined use Please The This The heating of the molding surface of the mold is Hot water , Hot water And three types of heating means of induction heating coil, Great freedom of heating So partly characteristic Is large Different products But In a single process certainly Since it can be manufactured and the variation in temperature distribution is reduced, stable characteristics can be obtained for each part. In addition, the portion with a high foaming ratio, which tends to have a long heating time, can be quickly heated by an induction heating coil in addition to the heated heating medium from the heating medium supply device. After molding, the cooling from the cooling medium supply device Since it can cool rapidly with the heat medium made, the molding cycle can be shortened to increase the production efficiency.
[0056]
If the temperature control pipe provided in at least one of both molds is divided into a plurality of parts, only a part of the molding surface can be heated and cooled by the heat medium, so only the necessary part is heated and cooled. As a result, production efficiency can be further increased.
[0057]
The cooling medium supply device is composed of a chiller water supply device that supplies chiller water cooled by using a refrigerant and a tower water supply device that supplies tower water cooled by air cooling. According to the above, the degree of freedom in partially changing the temperature distribution on the molding surface is further increased.
[0058]
Prior to operating the induction heating coil, according to the one that switches and operates the solenoid valve assembly so as to circulate and supply the high temperature water from the pressurized water supply device to the temperature control pipe arranged in the vicinity thereof, the induction heating coil is Since the molding surface of the first molding die in the vicinity of the first mold is first preheated with high-temperature water and then quickly heated by the induction heating coil, there is less variation in temperature distribution, and the rate of temperature rise is faster for that. Become.
[0059]
The solenoid valve assembly is switched and operated to circulate and supply the chiller water from the chiller water supply device to the temperature control piping after the circulation of high temperature water from the pressurized water supply device to the temperature control piping is stopped. Since the cooling rate when cooling the molded product increases, the molding cycle can be further shortened.
[0060]
Solenoid valve to stop the supply of the chiller water in the middle of the temperature drop of the mold due to the supply of the chiller water from the chiller water supply device in the previous section, and to circulate and supply the hot water from the hot water supply device to the temperature control piping According to the structure in which the assembly is switched and operated, the molding die is not overcooled by the chiller water, so that the heating time in the next step is shortened and the molding cycle can be further shortened.
[0061]
A circulation pipe having a bypass solenoid valve is connected to the pressurized water supply device, the hot water supply device, and the chiller water supply device, respectively, and the temperature control pipe is bypassed via the forward and return pipes each provided with a solenoid valve assembly. Connected to each circulation line at the position on both sides of the valve, and when each circulation line is not connected to any of the temperature control pipes, the bypass solenoid valve provided in the circulation line is opened. Therefore, even if each circulation pipe is not in communication with any of the temperature control pipes, the heat medium is circulated through the circulation pipes so that the temperature of the heat medium is stably maintained. In response to the switching operation of the solenoid valve assembly, a heat medium having a predetermined temperature is supplied from the beginning, and therefore, the operation delay can be reduced.
[0062]
The pressurized water supply device can adjust the temperature of the pressurized hot water, and the induction heating coil can adjust the output. The control range can be expanded, and the range of products that can be manufactured in a single process can be expanded.
[0063]
At least one temperature sensor for detecting the temperature of at least one of the molds is provided, and the control device supplies the hot water and outputs the induction heating coil based on the temperature detected by the temperature sensor and a predetermined procedure. According to the above-mentioned control, the accuracy of temperature control of the mold can be further improved.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a state in the middle of supplying molten resin in a molding apparatus to which one embodiment of a mold temperature control system according to the present invention is applied.
FIG. 2 is a cross-sectional view showing a state when the mold clamping of the molding apparatus shown in FIG. 1 is finished.
3 is a cross-sectional view showing a state when foaming and cooling of the molding apparatus shown in FIG. 1 are finished. FIG.
4 is a view showing a structure for supplying a heat medium to a temperature control pipe provided in a first mold (lower mold) of the embodiment shown in FIG. 1;
5 is a view showing a structure for supplying a heat medium to a temperature control pipe provided in a second molding die (upper die) of the embodiment shown in FIG.
6 is a time chart showing the operating state of each part in the embodiment shown in FIG. 1; FIG.
FIG. 7 is a cross-sectional view corresponding to FIG. 1 of an example of a molding apparatus provided with a heating mechanism according to the prior art.
8 is a cross-sectional view corresponding to FIG. 3 of the prior art shown in FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10,20 ... Mold, 10a, 20a ... Molding surface, 13, 23 ... Temperature control piping, 16, 26 ... Induction heating coil, 40 ... Pressurized water supply device, 40a1, 40a2 ... Hot water circulation conduit, 41 ... Hot water supply device 41a1, 41a2 ... warm water circulation pipe, 42 ... chiller water supply device, 42a1, 42a2 ... chiller water circulation pipe, 43 ... tower water supply device, 45a2 to 47a2 ... forward pipe, 45b2 to 47b2 ... return pipe, 50 ... Control device, V1, V2 ... Solenoid valve assembly, V19p, V29p ... Bypass solenoid valve, V19h, V29h ... Bypass solenoid valve, V19c, V29c ... Bypass solenoid valve, T11 to T23 ... Temperature sensor.

Claims (9)

In a molding apparatus that has a pair of molding dies each having a molding surface formed on the surfaces facing each other, and that molds the synthetic resin or the like by using the molding surfaces with the molding dies approaching and separating from each other. A temperature control pipe which is provided in at least one of the above and circulates a heat medium such as hot water or cold water to heat and cool the vicinity of the molding surface of the mold,
A heating medium supply device comprising a hot water supply device and a pressurized water supply device for supplying hot water as the heated heat medium and pressurized high-temperature water, respectively ;
A cooling medium supply device that supplies the cooled heat medium; and an electromagnetic valve assembly that includes the heating medium supply device and a plurality of electromagnetic valves that supply the heat medium from the cooling medium supply device to the temperature control pipe. An induction heating coil which is provided in the mold provided with the temperature control pipe and heats a part of the molding surface of the mold, and the molding apparatus, the electromagnetic valve assembly and the induction based on a predetermined procedure A mold temperature control system in a molding apparatus, comprising a control device for controlling the operation of a heating coil.   The mold temperature control system in the molding apparatus according to claim 1, wherein the temperature control pipe is divided into a plurality of portions. According to claim 1 or claim 2 wherein said cooling medium supply device consists of the tower water supply device for supplying a tower water cooled by Ruchi error water supply device and the air cooling to supply the cooled chiller water using a refrigerant Mold temperature control system in the molding equipment. The control device according to claim 1 wherein the induction before the heating coil to operate, the one in which the actuating switch the solenoid valve assembly to circulate supplying hot water from the pressurized water supply system to the temperature control pipe The mold temperature control system in the molding apparatus according to any one of claims 3 to 4 . The electromagnetic valve is configured to circulate and supply chiller water from the chiller water supply device to the temperature control pipe after the control device stops circulating high temperature water from the pressurized water supply device to the temperature control pipe. The mold temperature control system in a molding apparatus according to claim 3 or 4, wherein the assembly is switched and operated. The control device stops the supply of the chiller water in the middle of the temperature decrease of the mold due to the supply of the chiller water from the chiller water supply device, and supplies the hot water from the hot water supply device to the temperature control pipe. The mold temperature control system for a molding apparatus according to any one of claims 3 to 6 , wherein the electromagnetic valve assembly is switched and operated so as to be circulated. A pressurized water circulation line having a bypass electromagnetic valve is connected to the pressurized water supply apparatus, a hot water circulation line having a bypass electromagnetic valve is connected to the hot water supply apparatus, and a chiller water supply apparatus has a bypass electromagnetic valve. A chiller water circulation pipe is connected, and the temperature control pipe is connected to each circulation pipe at a position on both sides of the bypass solenoid valve via an outgoing pipe and a return pipe provided with the solenoid valve assembly, respectively. , wherein the control device either the respective circulation paths of the in a state that is not communicated any in communication even temperature control pipe made so as to open the bypass solenoid valve provided in the circulation pipeline claims 3 6 The mold temperature control system in the molding apparatus of Claim 1. The pressurized water supply system is capable of adjusting the temperature of the hot water under pressure, the induction heating coil according to any one of claims 1 to 7 it is possible to adjust the output Mold temperature control system in the molding equipment. At least one temperature sensor for detecting the temperature of at least one of the molds is provided, and the control device supplies the high-temperature water and the induction based on the temperature detected by the temperature sensor and the predetermined procedure. The mold temperature control system for a molding apparatus according to any one of claims 1 to 8, which controls an output state of the heating coil.

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