JP5937313B2 - Thermoforming apparatus and temperature control unit thereof - Google Patents

Description

  The present invention relates to a thermoforming device and its temperature control unit.

  A thermoforming apparatus using a hot plate has, for example, a control panel for controlling the entire apparatus, and a mold that moves up and down a continuous resin sheet that runs on the upper surface of the hot plate heated by a heater and stops intermittently. Is fixed by being lowered, heated by being brought into close contact with the hot plate by vacuum suction means and pressure air means, and thermoformed by differential pressure after heating. Here, in order to heat the hot plate uniformly, a large number of heaters are arranged below the hot plate, and the temperature detected by the thermocouple thermometer provided for each heater is set to each heater with the control panel. Feedback control of the energization amount is performed.

Note that the temperature control system described in Patent Document 1 includes a sheet heating unit, a heater allocation control unit, a system control unit, a heater control output unit, and the like. The sheet heating unit includes an upper heater group disposed in the upper mold and a lower heater group disposed in the lower mold, and a sheet-like object to be heated is inserted between the heater groups. The heater allocation control unit divides each of the upper and lower heater groups into one or a plurality of blocks. One temperature sensor is arranged for each of these blocks. That is, only one temperature sensor is arranged in a block composed of a plurality of heaters. The system control unit outputs an on / off signal for each heater to the heater control output unit so that the measured temperature of the temperature sensor matches the control temperature of each block. The heater control output unit performs on / off control of each heater based on the on / off signal from the system control unit.
As described above, the main body of feedback heating control of each heater is the system control unit, which is composed of a control panel that controls the entire apparatus.

  In the resin sheet heating control method described in Patent Document 2, a computer calculates a temperature control amount, and the computer instructs each control means of the temperature control amount via a sequencer to control the heat generation amount of the heater. That is, the main control unit of the amount of heat generated by the heater is a computer, and is composed of a control panel that controls the entire apparatus.

Japanese Patent Laid-Open No. 05-274048 JP 09-239823 A

  When a large number of heaters are provided in the thermoforming apparatus, it is necessary to provide a sequencer circuit in the control panel for controlling the energization amount of each heater so that the temperature detected by the temperature sensor matches the target temperature. In addition to the feedback control circuit for each heater, this sequencer circuit requires relays, wiring and terminals for each heater, wiring and terminals for each thermometer, and the like. In particular, the wiring required for a large number of heaters and thermometers complicates the sequencer circuit of the control panel, increasing the labor and cost of wiring assembly work, and thus increasing the cost of the thermoforming apparatus. .

  In the technique described in Patent Document 1, only one temperature sensor is arranged in a block composed of a plurality of heaters. As a result, the wiring required for the temperature sensor is slightly reduced. However, since the feedback control for the plurality of heaters in the block is reduced to one, the accuracy of the temperature control is lowered. In addition, since it is necessary to provide wiring for each heater, wiring for each temperature sensor, and the like in the control panel, the sequencer circuit of the control panel is complicated, and a large amount of labor and cost are required for wiring assembly work.

  The technique described in Patent Document 2 also requires that wiring for each heater, wiring for each temperature sensor, and the like be provided in the control panel, so that the sequencer circuit of the control panel is complicated, and a great amount of labor is required for assembling the wiring. There will be a cost.

  In view of the above, the present invention has an object of reducing wiring to a heating unit in a thermoforming apparatus.

To achieve the above object, the present invention is a thermoforming apparatus comprising a plurality of heating units for heating an object to be heated, and a temperature detection unit provided for each heating unit,
A main control unit for controlling thermoforming is provided at the first location, and a temperature control unit for controlling the heating output of the plurality of heating units is provided at a second location different from the first location. And
The main control unit
A first communication unit that bidirectionally communicates with the temperature control unit;
Comprises a temperature target for each of the temperature detecting unit that has received the operation input from said first communication unit and a temperature target output means for outputting to the temperature control unit,
The temperature control unit is
A second communication unit that communicates bidirectionally with the main control unit;
A temperature target input means for inputting a temperature target for each of the temperature detection units for which an operation input has been received from the main control unit via the first communication unit and the second communication unit ;
A drive output unit for driving the plurality of heating units;
A detection temperature input unit for inputting a detection temperature detected by the temperature detection unit for each heating unit;
Wherein every heating section, controlling the detected temperature inputted from the temperature detection unit of the input object to the detected temperature input from the drive output portion so as to approach the target temperature operation input accepted et al was from the main control unit Temperature control means for controlling the output to the target heating unit,
Having aspects which are communicably connected to the bidirectionally between the second communication unit and the first communication unit for the main control unit for controlling the thermoforming.

In addition, the present invention includes a plurality of heating units for heating an object to be heated, a temperature detection unit provided for each heating unit, and a first communication unit, which is provided at a first location and is thermoformed. A temperature control unit provided in a second place different from the first place in a thermoforming apparatus comprising:
A second communication unit that communicates bidirectionally with the main control unit;
A temperature target input means for inputting a temperature target for each of the temperature detection units for which an operation input has been received from the main control unit via the first communication unit and the second communication unit ;
A drive output unit for driving the plurality of heating units;
A detection temperature input unit for inputting a detection temperature detected by the temperature detection unit for each heating unit;
Wherein every heating section, controlling the detected temperature inputted from the temperature detection unit of the input object to the detected temperature input from the drive output portion so as to approach the target temperature operation input accepted et al was from the main control unit Temperature control means for controlling the output to the target heating unit,
Having aspects communicatively coupled bidirectionally between the second communication unit and the first communication unit for the main control unit for controlling the thermoforming.

That is, the temperature control unit including the drive output unit, the detected temperature input unit, and the temperature control unit is provided in a second location different from the location of the main control unit. The temperature control unit is provided with the temperature target input means. Thereby, the main control unit provided in the first location outputs the temperature target for each temperature detection unit that has received the operation input to the temperature control unit provided in the second location from the first communication unit. This eliminates the need to control the heating output for each heating unit, and eliminates the need to provide wiring for each heating unit.

Here, the thermoforming includes differential pressure forming such as pressure forming, vacuum forming and pressure forming.
The article to be heated includes a molding material that can be thermoformed, a hot plate, a molding die, and the like. When the material to be molded is heated by a heated hot plate or the like, the heating unit indirectly heats the material to be molded.
The heating unit includes a heater, a burner, and the like. Further, the heating unit may be composed of a plurality of heaters as well as a single heater. The output from the drive output unit to the heater to be controlled includes an energization amount to the heater, a voltage value applied to the heater, and the like. The energization amount to the heater includes an average current value flowing to the heater. The output from the drive output unit to the heating unit includes an analog amount, a digital value, and the like.
The temperature detection unit includes a thermocouple thermometer, a radiation thermometer, and the like. The detected temperature input to the detected temperature input unit includes an analog quantity, a digital value, and the like, and is not limited to the temperature value itself.
The temperature target includes a digital value, an analog amount, and the like, and is not limited to the temperature value itself.

According to the invention which concerns on Claim 1, the thermoforming apparatus which can reduce the wiring to a heating part can be provided.
In the invention according to claim 2, since the constant for controlling the heating output of the heating unit can be set from the main control unit, more suitable heating control can be performed according to the thermoforming conditions and the like.
In the invention which concerns on Claim 3, since the detection temperature for every temperature detection part can be visually recognized by the main control part, it becomes possible to perform temperature control of thermoforming easily.
In the invention which concerns on Claim 4, the temperature control unit of the thermoforming apparatus which can reduce the wiring to a heating part can be provided.

1 is a perspective view illustrating an appearance of a thermoforming device 1. 1 is a front view illustrating a thermoforming device 1. FIG. 4 is a vertical cross-sectional view illustrating the thermoforming apparatus 1 when the forming die 40 is at a predetermined separation position L13. FIG. 3 is a vertical cross-sectional view illustrating the thermoforming apparatus 1 when the mold 40 is at a predetermined proximity position L14. FIG. It is a top view which illustrates the hot platen 60 which has arrange | positioned the heater 79 and the thermometer 69 on the back side. 2 is a plan view schematically illustrating the appearance of a temperature control unit 100. FIG. 1 is a block diagram illustrating an outline of an electric circuit configuration of a thermoforming device 1. FIG. 3 is a timing chart illustrating the operation of the forming unit 20. 4 is a flowchart illustrating temperature control processing performed by a temperature control board 120. It is a figure which illustrates the list of measured values displayed on information output part 94. (A)-(c) is a block diagram which illustrates the composition of computer system 90. 4 is a flowchart illustrating temperature control unit management processing performed in a computer system 90. (A), (b) is a vertical sectional view which illustrates typically the thermoforming device concerning a modification. It is a block diagram which illustrates the outline of the electric circuit structure of the thermoforming apparatus which concerns on a comparative example.

  Embodiments of the present invention will be described below. Of course, the embodiments described below are merely illustrative of the present invention.

(1) Description of thermoforming device:
The thermoforming apparatus 1 illustrated in FIGS. 1 to 7 forms a sheet S <b> 1 by the forming unit 20 after the thermoforming sheet S <b> 1 is contact-heated with a hot plate 60. In FIG. 2, the direction from left to right is the predetermined conveyance direction D1, the left side is the upstream side of the sheet S1, and the right side is the downstream side of the sheet S1.

The thermoforming apparatus 1 illustrated in FIGS. 1 to 7 includes a plurality of heating units (heaters 79) for heating an object to be heated (hot plate 60), and temperatures provided for the respective heating units (heaters 79). A detection unit (thermometer 69). The main controller 2 that controls thermoforming is provided at the first location L1. A temperature control unit 100 for controlling the heating output (heat generation amount Q1) of the plurality of heating units (heaters 79) is provided in a second place L2 different from the first place L1.
As illustrated in FIG. 7, the main control unit 2 includes temperature target output means U <b> 21 that outputs a temperature target T <b> 1 for each temperature detection unit (thermometer 69) to the temperature adjustment unit 100.

As illustrated in FIG. 6, the temperature adjustment unit 100 includes a temperature target input unit U11, a drive output unit U12, a detected temperature input unit U13, and a temperature control unit U14.
The temperature target input means U11 inputs the temperature target T1 for each temperature detection unit (thermometer 69). The drive output unit U12 drives a plurality of heating units (heaters 79). The detected temperature input unit U13 inputs the detected temperature T2 detected by the temperature detecting unit (thermometer 69) for each heating unit (heater 79). For each heating unit (heater 79), the temperature control unit U14 brings the detected temperature T2 input from the temperature detection unit (thermometer 69) to be input to the detected temperature input unit U13 closer to the input temperature target T1. The output from the drive output unit U12 to the heating unit (79) to be controlled is controlled. For example, if the combination of the heater 79 and the thermometer 69 is identified by the number i, the drive output unit U12 brings the detected temperature T2i input from the i-th thermometer 69 closer to the temperature target T1i for each thermometer. The average current value (energization amount) to the i-th heater 79 is controlled.

  As described above, the main control unit 2 provided in the first location L1 outputs the temperature target T1 for each temperature detection unit (thermometer 69) to the temperature control unit 100 provided in the second location L2. It is not necessary to control the heating output (heat generation amount Q1) for each heating unit (heater 79), and it is not necessary to provide wiring for each heating unit (heater 79).

  The main control unit 2 illustrated in FIG. 7 further includes control constant output means U22 and detected temperature display means U23. The temperature control unit 100 illustrated in FIG. 6 further includes a control constant input unit U15 and a detected temperature information output unit U16.

  The control constant output means U22 outputs a control constant (P, I, D, etc.) of the heating output (heat generation amount Q1) to the temperature control unit 100. The control constant input means U15 inputs the control constant (P, I, D, etc.). The temperature control unit U14 controls the output from the drive output unit U12 to the plurality of heating units (heaters 79) using the input control constants (P, I, D, etc.). Thereby, the control constants (P, I, D, etc.) of the heating output (heat generation amount Q1) of the heating unit (heater 79) can be set from the main control unit 2, and depending on the thermoforming conditions, etc. It becomes possible to perform suitable heating control.

  The detected temperature information output means U16 outputs detected temperature information T3 corresponding to the detected temperature T2 for each temperature detector (thermometer 69) to the main controller 2. The detected temperature display means U23 displays detected temperature information T3 for each temperature detection unit (thermometer 69) input from the temperature adjustment unit 100. As a result, the main control unit 2 can visually recognize the detected temperature T2 for each temperature detection unit (thermometer 69), and can easily perform temperature control of thermoforming.

  A thermoforming apparatus 1 illustrated in FIG. 1 includes a sheet conveying mechanism 10. The sheet transport mechanism 10 transports a sheet (form material) S1 in a predetermined transport direction D1 passing through a predetermined molding position L10. The forming means 20 separates the hot plate 60 and the forming die 40 when the sheet S1 is conveyed by the sheet conveying mechanism 10, and the hot plate 60 and the forming die 40 when the sheet S1 is conveyed to the forming position L10. The sheet S <b> 1 is heated in close proximity to be molded in accordance with the shape of the molding surface 41 a.

  The sheet S1 to be molded only needs to be moldable, and may be a resin sheet made only of a resin such as a thermoplastic resin, a sheet made of a material in which an additive such as a filler is added to the resin, or a single layer sheet. Alternatively, a laminated sheet in which different materials are laminated may be used. Examples of the resin include polyethylene, polypropylene, polystyrene, poly (vinyl chloride), ABS resin (Acrylonitrile-butadiene-styrene resin), polyethylene terephthalate (Poly (ethylene terephthalate)) ), Polycarbonate, polyamide, acrylic resin, combinations thereof, and the like. The sheet S1 may be in the form of a sheet or film, and may be wound in a roll or cut to a predetermined length. The thickness of the sheet can be various thicknesses such as about 1 to 2 mm and about 0.25 to 1 mm, and a film of about 0.25 mm or less or a thick sheet may be used.

The sheet S1 can be thermoformed by differential pressure forming, press forming, or the like. The sheet conveyance direction D1 is set so that the sheet is stably conveyed in the horizontal direction. However, the sheet conveyance direction D1 may be shifted in the upward direction from the horizontal direction, shifted in the downward direction from the horizontal direction, or vertically upward. , It may be vertically downward.
In addition to the sheet, the material to be molded may be a massive material or the like.

  A sheet conveyance mechanism 10 shown in FIG. 1 includes a sheet supply mechanism 12 and a clamp conveyance mechanism 14. The sheet supply mechanism 12 can send out the sheet S1 wound in a roll shape in the transport direction D1 in a continuous state. The clamp conveyance mechanism 14 has clamp members 14a for clamping (gripping) both side edges of the formed sheet S2, and clamps both side edges of the sheet S2 formed at the forming position L10 in accordance with the forming timing. The sheet S1 clamped by the member 14a and pulled intermittently is pulled and conveyed in the conveying direction D1. The thermoforming apparatus 1 may be provided with a molded product take-out mechanism that cuts (cuts) the formed sheet S2 by a predetermined length.

With the above configuration, when the hot plate 60 and the mold 40 are separated from each other, the necessary amount of the roll-shaped sheet S1 is sequentially unwound from the sheet supply mechanism 12, and is conveyed in a predetermined conveyance direction D1, It is carried into the molding position L10. Here, the sheet S1 at the molding position L10 has the lower surface S1b in contact with the surface 61a of the hot plate 60, is supplied with heat from the hot plate 60, and is heated and softened. When the sheet S1 is conveyed to the forming position L10, the hot plate 60 and the forming die 40 come close to each other and sandwich the heated and softened sheet S1 at the forming position L10, and the sheet S1 is brought into close contact with the forming surface 41a by differential pressure forming. . Thereby, the sheet S1 is formed according to the shape of the forming surface 41a.
After the forming, when the hot plate 60 and the forming die 40 are separated from each other, both side edges of the formed sheet S2 which has already been carried out from the forming position L10 in the conveying direction D1 are clamped by the clamp members 14a at the clamp position L11, and the clamp is conveyed. The mechanism 14 moves horizontally from the clamp position L11 to the predetermined release position L12, and further conveys the sheet S2 by a predetermined amount in the conveyance direction D1. Then, the molded sheet S2 that has already been clamped is sent to, for example, a molded product take-out mechanism, cut at a predetermined length, and the molded product is taken out.

The hot plate 60 shown in FIGS. 3 to 5 etc. has a front plate 61 having a plurality of first vent holes 62 and a hot plate side vent which is in contact with the back surface 61b of the front plate 61 and is connected to the plurality of first vent holes 62. And a pedestal 65 in which a path 81 is formed.
The air holes 62 of the surface plate 61 are through holes penetrating from the surface 61a to the back surface 61b of the surface plate 61, and are arranged in different x and y directions on the surface 61a of the hot plate. Each vent hole 62 is acted on by negative pressure (so-called vacuum pressure) from the differential pressure supply means 25 (air is sucked), released from negative pressure supply (decompression), supplied with compressed air, The supply of compressed air is canceled. Note that the x direction and the y direction are preferably orthogonal to each other, but may intersect each other at an angle different from 90 °, such as 60 ° or more and less than 90 °, or 30 ° or more and less than 60 °. Further, the sheet conveyance direction D1 may be not only the x direction but also the direction deviated from the y direction or both the x and y directions. The surface plate 61 is disposed such that the surface 61a facing the forming die 40 contacts the lower surface S1b of the sheet S1 at the forming position L10, and heats and softens the sheet S1 carried into the forming position L10.

In the heat plate side ventilation path 81 in the pedestal 65, the groove on the surface 65 a is connected to the plurality of first ventilation holes 62, and the back surface 65 b side is connected to the heat plate side ventilation path 81 in the surface 70 a of the spacer 70. A surface plate 61 is placed and fixed on the surface 65 a of the pedestal 65.
The surface plate 61 and the pedestal 65 are made of, for example, metal and are formed in a rectangular plate shape.

  The molding means 20 shown in FIGS. 2 to 4 includes a molding die 40, a differential pressure supply ventilation path 80, a differential pressure supply means 25, and the like.

  The mold 40 includes a plurality of female molds (exchange molds) 41 and a mold base member 42, and faces the surface plate 61. Each female mold 41 is made of, for example, metal, has a molding surface 41a facing the hot plate 60, and has a ventilation hole (second ventilation hole) 40b on the molding surface. The mold base member 42 is made of, for example, metal, is formed in a substantially plate shape, and has a mold holding portion that detachably holds the plurality of female dies 41 on the lower surface. In the mold side ventilation path 82 formed in the mold base member 42, the groove on the lower surface is connected to the plurality of second ventilation holes 40 b, and the upper surface side is connected to the mold side ventilation path 82 on the lower surface 45 a of the upper table 45. The upper table 45 is made of, for example, metal, and the upper surface of the mold base member 42 is attached and fixed to the lower surface 45a.

  On the base 9 in contact with the floor, a plurality of columnar columns 55 are erected upward at positions where they do not come into contact with the conveyed sheet S1. The plurality of support columns 55 support the fixing member 51 from below while positioning the hot plate 60, and guide the reciprocating movement of the upper table 45 in the proximity and separation. The mold table drive mechanism 50 is attached to an upper portion 45b of the upper table 45 opposite to the lower surface 45a facing the heat plate, and the upper table 45 holding the mold 40 at the molding position L10 is reciprocated by the link mechanism 52. Let The fixing member 51 is made of, for example, metal, and is fixed to the tip end portion of the upright support column 55.

  The differential pressure supply ventilation path 80 includes a heat plate side ventilation path 81 that transmits the pressure of air from the hot plate side differential pressure supply circuit 26 (differential pressure supply means 25) and a mold side differential pressure supply circuit 27 (differential pressure supply). A mold side ventilation passage 82 for transmitting the pressure of air from the means 25). Since one of the hot plate side differential pressure supply circuit 26 and the mold side differential pressure supply circuit 27 can be omitted, one of the hot plate side ventilation path 81 and the mold side ventilation path 82 can be omitted. The differential pressure supply ventilation path 80 includes a resin tube such as a urethane tube, a resin hose, a resin tube, a metal tube, a pressure tube such as a pressure tube that can be connected to a joint or a valve, and a joint attached to the pressure tube. A combination with at least one of the valves can be used.

  The differential pressure supply means 25 supplies the differential pressure at which the pressure on the forming die 40 side is lower than the pressure on the hot plate 60 side to the sheet S1 in contact with the hot plate 60 from the differential pressure supply vent passage 80 and forms. Close to mold 40. For example, the surface plate 61 and the mold 40 are brought close to each other, the sheet upper surface S1a on the surface plate 61 and the outer periphery of the female mold 41 are brought into contact with each other, and the sheet upper surface S1a and the molding surface 41a recessed upwardly form a closed space. When the sheet is formed and pressurized air is supplied from the vent hole 62 of the surface plate 61 via the hot plate side vent path 81 and negative pressure is supplied from the vent hole 40b of the forming die via the mold side vent path 82, the sheet S1. Is compressed and vacuum formed in close contact with the forming surface 41a.

In order to provide a space for installing the heater for supplying heat to the hot plate 60 described above, a plurality of spacers 70 are erected at intervals from the back surface 65b of the pedestal 65 downward as shown in FIG. A plurality of spacers 70 are placed and fixed on the surface 75 a of the lower table 75. A part of the spacer 70 has a hot plate side ventilation path 81 extending from the front surface 70a to the back surface 70b. The spacer 70 can be made of various materials such as metal, ceramics, and resin, and a heat resistant material is preferable because a heater is disposed nearby.
The lower table 75 is made of, for example, metal, and the back surface 70b of the spacer 70 is attached and fixed to the front surface 75a.

As shown in FIG. 3 and the like, the heater 79 is fixed to the back surface 65b of the pedestal 65 while being separated from the surface 75a of the lower table 75 between the plurality of spacers 70. When energized, the heater 79 generates heat and heats the hot plate 60 from the pedestal 65 side. In the example of FIG. 5, it is shown that a total of 30 heaters 79, six in the x direction and five in the y direction, are arranged below the hot platen 60. The reason why a large number of heaters are provided on one hot plate is to uniformly heat the hot plate.
The pedestal 65 is provided with a thermometer 69 for detecting the temperature of the surface plate 61 for each heater 79. A thermocouple thermometer or the like can be used as the thermometer 69. In the example of FIG. 5, it is shown that 30 thermometers 69 in total in the x direction and 5 in the y direction are arranged below the surface plate 61. In order to heat the hot plate uniformly, the energization amount to each heater is feedback controlled so that the temperature detected by the thermometer provided for each heater matches the target temperature.
The heating temperature of the hot plate is set according to the material, thickness, and the like of the sheet, and can be set to, for example, the temperature at which the sheet softens or more and the temperature at which it melts.

  As shown in FIGS. 1, 2, etc., the temperature control unit 100 is provided at a second location L <b> 2 that is closer to the heater 79 than the first location L <b> 1 of the main control unit 2. The temperature control unit 100 shown in FIG. 6 includes a temperature control board 120, a communication connector 128, a drive output unit U12, a detection temperature input terminal group 140, and the like on a conductive ground plate 110 such as a metal plate. ing.

The temperature control board 120 is formed with wiring having a microcomputer, a power input terminal 121, and the like on a printed circuit board, and executes the temperature control process shown in FIG. Details of this temperature control process will be described later. The microcomputer has an internal bus, a CPU (Central Processing Unit) 122, a ROM (Read Only Memory) 123, a RAM (Random Access Memory) 124, a timer circuit 125, an A / D (analog / digital) conversion circuit 126, a communication. Units 127, etc. are connected. The temperature control board 120 operates by inputting a DC voltage E2 (for example, 24V) of the DC power supply to the power input terminal 121, and controls the operation of the entire temperature control unit 100. The A / D conversion circuit 126 is connected to the detected temperature input terminal group 140. For each heater 79, the temperature control board 120 determines the operation amount of the relay 134 to be output so that the detected temperature T2i input from the thermometer 69 to be input is close to the temperature target T1i. Is output.
The connector 128 is connected to the communication unit 127 and is connected to the main control unit 2 via, for example, a communication cable. As the connector 128, a connector such as RS-485 such as a serial communication standard or a parallel communication standard can be used.

The drive output unit U12 includes a power input terminal 132, a plurality of relays 134, and a heater output terminal group 136, and drives each heater 79 individually.
The power input terminal 132 inputs an AC voltage E1 of an AC power supply such as a commercial AC 200 V, for example, and supplies the AC voltage E1 to the input terminal of each relay 134.

The relay 134 is provided for each heater 79, and supplies the AC voltage E1 to the heater 79 when the on / off signal input from the temperature control board 120 is on, and supplies the AC voltage E1 to the heater 79 when the on / off signal is off. The supply of AC voltage E1 is cut off. When the ratio of the on period of the on / off signal is R1 (0 ≦ R1 ≦ 1) and the amount of current flowing through the heater 79 during the on period is Ion (A), the average current value flowing through the heater 79 is approximately R1 × Ion. . As the relay 134, an SSR (solid state relay) or the like can be used.
The heater output terminal group 136 has a heater output terminal 137 for each heater 79, and is connected to a power line (wiring 79 a) of the heater 79. Each heater output terminal 137 supplies an AC voltage E <b> 1 input from the output unit of the corresponding relay 134 to the heater 79.

The detection temperature input terminal group 140 has a detection temperature input terminal 141 for each thermometer 69 and is connected to a wire 69 a to the thermometer 69. Each detected temperature input terminal 141 receives a voltage corresponding to the detected temperature from the corresponding thermometer 69 and outputs this voltage to the temperature control board 120.
6 has 16 combinations of the relay 134, the heater output terminal 137, and the detected temperature input terminal 141. As shown in FIG. 5, when there are 30 combinations of heaters 79 and thermometers 69, if two temperature control units 100 are prepared, all the heaters 79 can be individually heated and controlled.

  Operation | movement of the thermoforming apparatus 1 provided with the temperature control unit 100 mentioned above is controlled by the computer system 90 shown in FIG. 7, for example. The computer system 90 is electrically connected to the temperature control unit 100, the sheet conveying mechanism 10, the forming mechanism 21 constituting the forming means 20, and the like. The computer system 90 includes a central control circuit 91 that controls the operation of the entire system, for example, a communication unit 92 that is connected to the connector 128 of the temperature control unit via a serial communication standard communication cable, and a sheet that controls the operation of the sheet conveying mechanism 10. The conveyance control part 93a, the shaping | molding control part 93b which controls operation | movement of the shaping | molding mechanism 21, the information output part 94, the operation part 95, etc. are provided.

The central control circuit 91 is a circuit in which a CPU 91a, ROM 91b, RAM 91c, timer circuit 91d, nonvolatile memory 91e, and the like are connected to an internal bus. The information output unit 94 is configured by, for example, a display, an audio output device, or a printer, and outputs various types of information indicating the operation settings of the thermoforming apparatus 1 and the various settings that have received operation input from the user by display or the like. FIG. 10 illustrates a list of measurement values displayed on the information output unit 94. The operation unit 95 includes, for example, a plurality of buttons, and receives operation input from the user.
Here, the computer system 90 constitutes a part of the forming means 20. The computer system 90 provided with the communication unit 92 constitutes a temperature target output unit U21 and a control constant output unit U22. The computer system 90 provided with the information output unit 94 constitutes detected temperature display means U23.

The computer system 90 can have various configurations.
A computer system 90 illustrated in FIG. 11A is connected to a personal computer 90a, a touch panel 90b connected to the personal computer 90a by a LAN (Local Area Network), for example, and the temperature control unit 100, and the touch panel 90b. And a sequencer 90c to which the sheet conveying mechanism 10 and the forming mechanism 21 are connected. For example, the touch panel 90b receives an operation on a soft switch or a lamp displayed on the liquid crystal display and outputs an operation signal corresponding to the operation to the sequencer 90c. The sequencer 90c controls the operations of the sheet transport mechanism 10 and the forming mechanism 21 according to an operation signal from the touch panel 90b.

In the computer system 90 illustrated in FIG. 11B, the function of the touch panel 90b illustrated in FIG. 11A is also provided in the personal computer 90a.
In the computer system 90 illustrated in FIG. 11C, all functions are provided in the control panel 90d. The operation panel 90e receives, for example, operations on soft switches and lamps displayed on the liquid crystal display.

  As illustrated in the timing chart of FIG. 8, in the initial state, the computer system 90 turns off the clamp of the sheet S <b> 2 by turning off the sheet clamp of the clamp member 14 a, and moves the clamp conveyance mechanism 14 to the upstream side. A state where the predetermined clamping position L11 is set, the molding die 40 is moved to a predetermined separation position L13, and the supply of negative pressure or air pressure from the hot plate side differential pressure supply circuit 26 and the mold side differential pressure supply circuit 27 is released. I have to. In this state, the computer system 90 turns on the sheet clamp of the clamp member 14a and clamps both side edges of the sheet S2 to the clamp conveyance mechanism 14 (timing t1). At timings t2 to t3, the clamp transport mechanism 14 is moved from the clamp position L11 to a predetermined release position L12 on the downstream side. Then, the sheets S1 and S2 are conveyed in a predetermined amount in the conveyance direction D1, and the unformed sheet S1 is carried into the forming position L10. At timing t4, the sheet clamp of the clamp member 14a is turned off and the clamp of the sheet S2 is released. Note that the clamp transport mechanism 14 is moved from the release position L12 to the upstream clamp position L11 at a predetermined timing before returning to the timing t2.

At timing t5, a negative pressure is applied from the hot plate side differential pressure supply circuit 26 to the vent hole 62 of the hot plate, and the sheet S1 at the forming position L10 is brought into close contact with the surface plate 61 to be heated and softened. At timings t6 to t7, as shown in FIG. 4, the upper table 45 is lowered by the mold table driving mechanism 50, the molding die 40 is moved to a predetermined proximity position L14, and the hot plate 60 and the molding die 40 are brought close to each other. Let At timings t8 to t9, compressed air is supplied from the hot plate side differential pressure supply circuit 26 to the hot plate vent 62 and negative pressure is applied from the mold side differential pressure supply circuit 27 to the mold vent 40b to soften the heat. The sheet S1 in a state is brought into close contact with the concave molding surface 41a. Since the temperature of the female die 41 is lower than that of the surface plate 61, the sheet in close contact with the molding surface 41a is cooled and solidified. As a result, the sheet is vacuum-pressure formed, and a molded product before cutting is formed.
When there is no hot plate side differential pressure supply circuit 26, pressure air is supplied from the mold side differential pressure supply circuit 27 to the mold vent 40b at timing t5, and from the mold side differential pressure supply circuit 27 at timing t8 to t9. When a negative pressure is applied to the vent 40b of the mold, the sheet can be vacuum formed. When the mold side differential pressure supply circuit 27 is not provided, the sheet can be formed by pressure forming by supplying compressed air from the hot plate side differential pressure supply circuit 26 to the vent hole 62 of the hot plate at timings t8 to t9.

When the supply of pressurized air to the vent hole 62 of the hot plate is released at timing t9 and the supply of negative pressure to the ventilation hole 40b of the mold is released, the upper table 45 is moved by the mold table drive mechanism 50 from timing t10 to t11. The mold 40 is moved to a predetermined separation position L13 shown in FIG. 3, and the hot plate 60 and the mold 40 are separated from each other.
Thus, one cycle is completed, and thereafter, differential pressure molding using a hot plate can be continuously performed from the sheet by repeating the timings t1 to t11. Note that the order of the timings of the operations described above can be changed as appropriate.

(2) Operation, action and effect of temperature control unit:
For example, when the power is supplied, the main control unit 2 starts supplying the DC voltage E2 to the temperature control unit 100 and starts the temperature control unit management process shown in FIG. This process is performed mainly by the central control circuit 91, and is performed in parallel with other processes by multitasking. Here, steps S202 to S204 correspond to temperature target output means U21 and control constant output means U22, and steps S206 to S208 correspond to detected temperature display means U23. Hereinafter, the description of “step” is omitted.

When the temperature control unit management process is started, the main control unit 2 receives operation inputs of various set values from the operation unit 95 (S202). The set value includes a temperature target T1i for each thermometer 69, a control constant, and the like. For example, if the temperature targets T1i are all 160 ° C., the operator may input 160 ° C. for all the thermometers 69. When performing PID control (proportional plus integral plus derivative control), which is a type of feedback heating control, the control constants include P (proportional gain), I (integral time), and D (differential time) constants. . When the feed control is included in the heating control, the control constant includes the set value FF of the feed forward control. In addition to these, the control constant may include a response speed to the temperature target T1i, a maximum value of the ON ratio R1 of the ON / OFF signal to each relay 134, and the like. Of course, the P, I, and D constants are not essential for the control constant, and the ON ratio Rlow and the detected temperature ≧ the temperature target (or the detected temperature> the temperature for the detected temperature <the temperature target (or the detected temperature ≦ the temperature target). For example, an ON ratio Rhigh (0 ≦ Rhigh <Rlow ≦ 1) for the target) may be set as a control constant, and various constants may be set as control constants according to the type of heating control.
In S204, the received set value is output from the communication unit 92 to the temperature adjustment unit 100 together with the output request.

For example, when the supply of the DC voltage E2 from the main control unit 2 to the power input terminal 121 is started, the temperature control board 120 of the temperature control unit starts the temperature control process shown in FIG. This process is performed in parallel with other processes by multitasking. Here, S102 to S104 correspond to the temperature target input means U11 and the control constant input means U15, S108 to S110 correspond to the temperature control means U14, and S112 correspond to the detected temperature information output means U16.
When the temperature control process starts, the temperature control board 120 determines whether or not there is a setting value input request from the main control unit 2 (S102). When there is a request for input of a set value, the temperature control board 120 inputs a set value such as a temperature target T1i for each thermometer 69 or a control constant via the connector 128 and stores it in the RAM 124 (S104).

  In S106, the detected temperature T2i is read from the detected temperature input terminal 141 for each thermometer 69 via the A / D conversion circuit 126, and detected temperature information T3i corresponding to the detected temperature T2i is acquired. The detected temperature information T3i can be, for example, a numerical value with a predetermined number of bits (for example, 16 bits) corresponding to the detected temperature T2i of the analog voltage.

  In S108, the operation amount (ON ratio R1i) is determined for each heater 79, that is, for each relay 134. The operation amount (R1i) is an output amount of the temperature control board 120, and is added to the relay 134 in order to control the temperature of the thermometer 69. The operation amount (R1i) of the i-th relay 134 is obtained by using the control constant (P, I, D, etc.) stored in the RAM 124, and the detected temperature T2i input from the input thermometer 69 as a temperature target. Decide to match T1i. Thereby, the average current value (energization amount) of each heater 79 is determined.

  For example, in the case of feedback heating control, P (proportional gain) is used if the detected temperature information T3i does not reach the vicinity of the temperature target T1i (for example, T1i-T3i is equal to or less than a predetermined positive value TH1), such as immediately after the power is turned on. Thus, the ON ratio R1i may be determined according to the difference between the temperature target T1i and the detected temperature T2i. If the detected temperature information T3i has reached the vicinity of the temperature target T1i, D (differential time) is used so as to reduce the change in the detected temperature information T3i, and the difference between the temperature target T1i and the detected temperature T2i is reduced. Thus, the ON ratio R1i may be determined using I (integration time). When performing simple feedback heating control, when T3i <T1i (or T3i ≦ T1i), the ON ratio R1i of the i-th ON / OFF signal to the relay 134 is detected temperature <temperature target (or detection temperature ≦ temperature target). The ON ratio Rlow is increased to increase the average current value of the heater 79. When T3i ≧ T1i (or T3i> T1i), the ON ratio R1i of the ON / OFF signal to the relay 134 at the i-th is detected temperature ≧ temperature target ( Alternatively, the average current value of the heater 79 may be increased by decreasing the ON ratio Rhigh so that the detected temperature> the temperature target).

In S110, each relay 134 is controlled by outputting an ON / OFF signal of the determined ON ratio R1i to each relay 134. When the i-th relay 134 receives an ON / OFF signal corresponding to the ON ratio R1i, the i-th relay 134 supplies the AC voltage E1 to the i-th heater 79 when the ON / OFF signal is ON, and the i-th relay 134 when the ON / OFF signal is OFF. The supply of the AC voltage E1 to the heater 79 is cut off. In the i-th heater 79, the heat generation amount Q1i (the unit is cal, for example) is controlled by a current having an average current value corresponding to the ON ratio R1i. This calorific value Q1i is the heating output of the i-th heater 79.
Thus, for each heater 79, the output from the drive output unit U12 to the control target heater 79 is controlled so that the detected temperature T2 input from the input target thermometer 69 approaches the temperature target T1.

  In S112, measurement information such as detected temperature information T3i for each thermometer 69 is output from the communication unit 127 to the main control unit 2 together with the output request. The measurement information may include an average current value of each heater 79, an alarm, and the like in addition to the detected temperature information T3. The average current value of each heater 79 may be a current value obtained from the ON ratio R1i of the ON / OFF signal, or may be a current value detected by an ammeter provided for each heater 79. The alarm includes an alarm that the detected temperature exceeds the upper limit, an alarm that the average current value of the heater exceeds the upper limit, and the like.

  The main control unit 2 determines whether or not there is a measurement information input request from the temperature control unit 100 in S206 of FIG. When there is a request for input of measurement information, the main control unit 2 inputs measurement information such as detected temperature information T3i for each thermometer 69 via the connector 128, and outputs it to the information output unit 94 (S208). FIG. 10 illustrates an information output unit 94 that displays a list of detected temperature information T3 for each thermometer 69 and average current values for each heater 79 as measurement information.

In S210, the main control unit 2 determines whether or not to end the temperature control unit management process. When the process is not terminated, such as continuing to manufacture a thermoformed product, the processes of S206 to S210 are repeated to display updated measurement information. When the production of the thermoformed product is finished, the temperature control unit management process is finished.
The temperature control board 120 also determines whether or not to end the temperature control process in S114. When the process is not completed, such as continuing to manufacture a thermoformed product, the processes of S106 to S114 are repeated, and the control of the heat generation amount Q1i of each heater 79 and the output of measurement information are continued. When an instruction to end the temperature control process is input from the main control unit 2, the temperature control process ends.

  FIG. 14 is a block diagram illustrating an outline of an electric circuit configuration of a thermoforming apparatus according to a comparative example. A computer system 900 of the thermoforming apparatus includes a central control circuit 901, a sheet conveyance control unit 941, a forming control unit 942, an information output unit 943, an operation unit 944, a detected temperature input unit 910, a drive output unit 920, and a temperature. A control unit 930 is required. The detection temperature input unit 910 requires a detection temperature input terminal group 912 including a large number of detection temperature input terminals 913. The drive output unit 920 requires a heater output terminal group 922 including a large number of relays 924 and a large number of heater output terminals 923. The temperature control unit 930 controls the energization amount from the drive output unit 920 to the heater 79 so that the detected temperature input from the thermometer 69 to the detected temperature input unit 910 matches the temperature target for each heater 79. Since the computer system 900 is located far from the location where the thermometer 69 and the heater 79 are installed, long wires 69 a and 79 a to a large number of thermometers 69 and heaters 79 are required. Also, the wiring and terminals necessary for a large number of thermometers 69 and heaters 79 complicate the electric circuit of the computer system 900, increase the labor and cost of assembling work such as wiring, and consequently the thermoforming apparatus. Increases costs.

In the thermoforming apparatus illustrated in FIG. 7, a temperature adjustment unit 100 including a drive output unit U12, a detected temperature input unit U13, and a temperature control unit U14 is provided in a second location L2 different from the location L1 of the main control unit 2. It has been. In particular, the location L2 of the temperature control unit is closer to the heater 79 than the location L1 of the main control unit. Therefore, the wirings 69a and 79a to many thermometers 69 and heaters 79 can be shorter than the comparative example. The main control unit 2 provided in the first place L1 outputs a temperature target T1 for each thermometer 69 to the temperature control unit 100 provided in the second place L2, thereby generating a calorific value Q1 for each heater 79. Need not be controlled, and it is not necessary to provide wiring for each heater 79.
As described above, the present technology can reduce wiring to the heating unit and the temperature detection unit.

(3) Modification:
In the forming means, a hot plate may be disposed on the upper surface side of the sheet, and a mold may be disposed on the lower surface side of the sheet. When the sheet is conveyed in the vertical direction, the hot plate and the mold may be arranged at the same height.
The hot plate disposed on the one surface side of the sheet may contact the one surface of the sheet or may contact the one surface of the sheet without contacting. In addition, when heating a sheet | seat, you may heat a sheet | seat by combined use of radiation heating or contact heating and radiation heating besides contact heating. The mold disposed on the other surface side of the sheet may contact the other surface of the sheet or may not contact the other surface of the sheet.
When the hot plate and the mold are brought close to and away from each other, only the hot plate or both the hot plate and the mold may be moved. In addition, when the hot plate and the mold are brought close to and away from each other, the position of the sheet is not changed, and the sheet may be moved in the direction of the mold, or the sheet may be moved in the direction of the hot plate.
The mechanism for moving the mold table close to and away from the hot plate may be various crank mechanisms, a mechanism using a cylinder such as an air cylinder or a hydraulic cylinder, and the like.
The hot plate may be a single member in which the surface plate and the pedestal are integrated.

The object to be heated may be a molding material, a molding die, or the like in addition to a hot plate.
The heating unit may be a mechanism for supplying hot air, a mechanism for burning fuel such as gas, or the like.
The temperature detection unit may be a radiation thermometer, a resistance temperature sensor, or the like.
The measurement location of the temperature detection unit may be a hot plate, a molding material, a molding die, etc., a heated object directly heated by the heating unit, or a heating object heated by the heated object. The thing etc. which are heated indirectly by a part may be sufficient.
The heater wiring 79a and the heater output terminal 137 may be fixed so as not to be separated. The output unit exemplified by the heater output terminal may be a simple wiring or the like provided in the temperature control unit.
The thermometer wiring 69a and the detection temperature input terminal 141 may be fixed so as not to be separated. The detection temperature input unit exemplified by the detection temperature input terminal may be a simple wiring or the like provided in the temperature control unit.

  FIG. 13A is a vertical cross-sectional view schematically illustrating a modified thermoforming apparatus including the heating apparatus 210 and the forming apparatus 220. The heating device 210 includes a plurality of combinations of heaters 79 and radiation thermometers (69) on the top and bottom. When the continuous sheet (S1) is conveyed in the conveyance direction D1 and carried into the heating device 210, it is heated and softened. When the softened sheet S1 is further transported in the transport direction D1 and carried into the forming apparatus 220, a thermoformed product is formed by the forming die 40. The temperature control unit 100 is installed in a place near the upper heater 79 and a place near the lower heater 79, that is, in the heating device 210 closer to the heater 79 than the main control unit. As described above, when the temperature control unit 100 is installed in a place different from the main control unit, an effect of reducing wiring to the heater 79 and the thermometer 69 can be obtained.

  FIG. 13B is a vertical cross-sectional view schematically illustrating a modified thermoforming apparatus in which the cut sheet (S1) is sandwiched between the mold 40 and the clamp 44 facing each other. The plurality of heaters 79 are provided in the mold 40, and a radiation thermometer (69) for each heater 79 is provided on the clamp 44 side. Each thermometer 69 detects the surface temperature of the sheet S1. The temperature control unit 100 is installed in a molding apparatus close to the heater 79, that is, a place closer to the heater 79 than the main control unit. As described above, when the temperature control unit 100 is installed in a place different from the main control unit, an effect of reducing wiring to the heater 79 and the thermometer 69 can be obtained.

In addition, only the basic portions U11, U12, U13, and U14 of the temperature control unit 100 can provide the effect of reducing the wiring to the heating unit.
In other words, the above-described basic actions and effects can be obtained even with a technique or the like that does not have the constituent requirements according to the dependent claims but includes only the constituent requirements according to the independent claims.

As described above, according to the present invention, it is possible to provide useful temperature control unit technology and the like according to various aspects.
In addition, it is also possible to implement the present invention by mutually replacing the configurations disclosed in the above-described embodiments and modifications, and changing the combination. It is also possible to carry out the present invention by substituting each component disclosed in the above or changing the combination. Therefore, the present invention is not limited to the above-described embodiments and modifications, and includes configurations in which the configurations disclosed in the publicly known technology and the above-described embodiments and modifications are mutually replaced or combinations thereof are changed. It is.

DESCRIPTION OF SYMBOLS 1 ... Thermoforming apparatus, 2 ... Main control part, 20 ... Molding means,
60 ... Hot plate, 61 ... Surface plate, 65 ... Pedestal,
69 ... thermometer (temperature detection part), 69a ... wiring,
70 ... spacer, 75 ... lower table,
79 ... heater (heating part), 79a ... wiring,
90 ... computer system,
100 ... temperature control unit, 110 ... ground plate,
120 ... temperature control board, 121 ... power input terminal,
128 ... Connector,
132: power input terminal, 134: relay,
136 ... heater output terminal group, 137 ... heater output terminal,
140: Detection temperature input terminal group, 141: Detection temperature input terminal,
L1 ... first place, L2 ... second place,
S1 ... sheet (material to be molded), S2 ... sheet after molding,
U11 ... temperature target input means, U12 ... drive output unit, U13 ... detected temperature input unit,
U14 ... temperature control means, U15 ... control constant input means, U16 ... detected temperature information output means,
U21 ... temperature target output means, U22 ... control constant output means, U23 ... detected temperature display means.

Claims (4)

A thermoforming apparatus comprising a plurality of heating units for heating an object to be heated, and a temperature detection unit provided for each heating unit,
A main control unit for controlling thermoforming is provided at the first location, and a temperature control unit for controlling the heating output of the plurality of heating units is provided at a second location different from the first location. And
The main control unit
A first communication unit that bidirectionally communicates with the temperature control unit;
Comprises a temperature target for each of the temperature detecting unit that has received the operation input from said first communication unit and a temperature target output means for outputting to the temperature control unit,
The temperature control unit is
A second communication unit that communicates bidirectionally with the main control unit;
A temperature target input means for inputting a temperature target for each of the temperature detection units for which an operation input has been received from the main control unit via the first communication unit and the second communication unit ;
A drive output unit for driving the plurality of heating units;
A detection temperature input unit for inputting a detection temperature detected by the temperature detection unit for each heating unit;
Wherein every heating section, controlling the detected temperature inputted from the temperature detection unit of the input object to the detected temperature input from the drive output portion so as to approach the target temperature operation input accepted et al was from the main control unit Temperature control means for controlling the output to the target heating unit,
Thermoforming apparatus characterized by being communicatively connected bidirectionally between the second communication unit and the first communication unit for the main control unit for controlling the thermoforming. The main control unit includes control constant output means for outputting the heating output control constant from the first communication unit to the temperature control unit,
The temperature control unit includes control constant input means for inputting the control constant from the main control unit via the first communication unit and the second communication unit ,
2. The thermoforming apparatus according to claim 1, wherein the temperature control unit controls output from the drive output unit to the plurality of heating units using the input control constant. The temperature control unit includes detection temperature information output means for outputting detected temperature information corresponding to the detected temperature for each temperature detection unit from the second communication unit to the main control unit,
The main control unit includes detection temperature display means for displaying detected temperature information for each temperature detection unit input from the temperature control unit via the second communication unit and the first communication unit. The thermoforming apparatus according to claim 1 or 2. A plurality of heating units for heating an object to be heated, a temperature detection unit provided for each heating unit, and a main control unit that has a first communication unit and is provided in a first place to control thermoforming And a temperature control unit provided in a second place different from the first place in a thermoforming apparatus comprising:
A second communication unit that communicates bidirectionally with the main control unit;
A temperature target input means for inputting a temperature target for each of the temperature detection units for which an operation input has been received from the main control unit via the first communication unit and the second communication unit ;
A drive output unit for driving the plurality of heating units;
A detection temperature input unit for inputting a detection temperature detected by the temperature detection unit for each heating unit;
Wherein every heating section, controlling the detected temperature inputted from the temperature detection unit of the input object to the detected temperature input from the drive output portion so as to approach the target temperature operation input accepted et al was from the main control unit Temperature control means for controlling the output to the target heating unit,
Temperature control unit, characterized in that communicatively coupled bidirectionally between the second communication unit and the first communication unit for the main control unit for controlling the thermoforming.

Images