JP3282436B2 - Injection compression molding method and injection compression molding apparatus - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an injection compression molding method, and more particularly to an injection compression molding method for improving the operability and supplying a high-quality molded product continuously and stably.

[0002]

2. Description of the Related Art When performing injection compression molding using an injection molding apparatus that performs mold clamping by a toggle mechanism, (1) mold clamping is completed in a state where the toggle mechanism is fully extended, and in this state, a predetermined amount is applied to a mold. Keep a gap.
Then, after the molten resin is injected and filled into the mold, compression is performed by a hydraulic cylinder for compression or the like separately provided on the movable platen or the fixed platen. (2) In the toggle-type mold clamping mechanism, the crosshead position of the toggle mechanism and the displacement amount of the movable platen (mold) are set so that a relatively small mold clamping force equal to or less than the maximum mold clamping force is obtained when the toggle mechanism is not fully extended. Stopping the toggle mechanism by control based on the set value converted to the position of the crosshead using the geometric relationship of the opening amount and the mold clamping force), clamping the mold, and then injecting the molten resin into the mold Thereafter, compression is performed with the toggle mechanism fully extended by re-driving.

[0003]

The conventional injection compression molding has the following problems. (1) In the method in which the mold clamping is completed with the toggle mechanism fully extended and the molten resin is injected and filled in the mold in this state, no special modification is required on the toggle mechanism side. Separately, a hydraulic cylinder dedicated to compression is required, which leads to an increase in complexity and cost of the molding machine. (2) In the method of controlling the mold clamping with a set value obtained by converting the mold opening amount and the mold clamping force into the crosshead position based on the geometric relationship of the toggle mechanism, the toggle mechanism as described in (1) above is used. The geometric relationship between the crosshead position of the toggle mechanism and the amount of displacement of the movable platen, in other words, the mold opening and the mold clamping force, depends on the thickness of the mold to be mounted, although it does not require a dedicated hydraulic cylinder for compression. Since the relational expression is infinite due to the combination of the die height adjustment value that increases or decreases the maximum generated mold clamping force at the completion of mold clamping according to the mold thickness setting value and the size of the mold, the geometrical shape is different for each mold used. Operability is extremely poor and impractical. If means for programming the geometric relationship of the toggle mechanism and performing automatic arithmetic processing are incorporated to obtain a desired result by arithmetic processing on the number of combinations of various variables close to infinity, the complexity of software and hardware becomes complicated. In addition, there is a problem that the size is unavoidable and the cost is high, which is not appropriate.

(3) Further, in all of the conventional methods, the injection filling is performed after the mold is set to a predetermined mold clamping force or a mold opening amount, and the toggle mechanism is operated at a high speed. In addition, since accurate position stop cannot be performed due to the inertial force, the operation is performed at a low speed. As a result, the molding cycle tends to be equal or longer than that of a normal molding method, and thus there is a disadvantage that productivity is low. SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to provide a simple control of only injection pressure and pressure control of a mold clamping force without largely modifying a molding machine of an existing toggle mechanism. Injection molding can be performed with high precision, and non-defective products can be supplied stably in a shorter molding cycle.

[0005]

In order to solve the above problems, according to the first aspect of the present invention, there is provided an injection molding apparatus which performs mold clamping by using a toggle mechanism, and uses an injection mechanism during an injection filling step. Calculates the amount of shrinkage due to cooling and solidification of the resin in advance, and controls the injection pressure with the injection pressure that can fill the amount of resin with the amount of shrinkage into the mold cavity. A mold clamping force that allows the mold to open by the tie bar extending to the mold opening amount corresponding to the cooling, solidifying, and shrinking amount of the resin due to the resin pressure filled in the cavity is set, and is set via a toggle mechanism. The movable mechanism is advanced to extend the toggle mechanism from a state where both molds are touched in a state where the toggle mechanism is not fully extended to the set value of the mold clamping force, and the mold of the mold clamp mechanism is used in the injection filling step. Performs injection filling operation while force setting operation, and so as to boosted clamping force by advancing the movable platen which is retracted during injection filling operation after completion injection filling. Further, in the second invention, the stroke of the mold clamping cylinder connected to the toggle mechanism is set by using the mold clamping force detecting unit incorporated in the tie bar in advance to detect a state in which both molds are touched, After the toggle mechanism is extended until the set mold clamping force is reached, the hydraulic pressure of the mold clamp cylinder is controlled so as to maintain the stroke position of the mold clamp cylinder that has reached the set mold clamp force. Further, the injection compression molding apparatus of the third invention comprises an injection filling amount setting means and an injection pressure setting means, an injection control section for performing injection filling based on the both setting means, and cooling of the resin by the injection filling. Mold clamping force setting means for setting a mold clamping force that allows the mold to open by extending the tie bar to the mold opening amount corresponding to the amount of solidification shrinkage, and a mold clamping cylinder stroke sensor for detecting the stroke of the mold clamping cylinder A mold clamping force detecting unit incorporated in the tie bar for detecting a mold clamping force in a mold clamping process, and a mold touch point setting unit for setting a mold touch point based on a detection signal of the mold clamping force detecting unit. A mold clamping control unit that compares a set value of the mold clamping force setting means with a detection signal of the mold clamping cylinder stroke sensor to control a stroke of a mold clamping cylinder connected to a toggle mechanism to perform mold clamping. In addition, the mold touch point setting unit has a function of transmitting a mold clamping force setting start signal to the mold clamping control unit after the origin setting is completed and transmitting an injection start signal to the injection control unit. An injection / fill completion detecting unit for transmitting a signal, and a comparison control unit for transmitting a mold clamping pressure increasing signal to the mold clamping control unit based on a detection signal from the injection / fill completion detecting unit are provided.

[0006]

In the injection filling process, the filling is controlled so that the filling can be performed at a high speed in the initial stage of filling because the flow resistance of the resin in the mold cavity is small, and in the latter stage of the filling, the flow resistance of the resin increases so that the filling speed is increased. Is naturally decelerated, so that the resin has a continuous speed gradient automatically during resin filling, and can be an ideal natural filling flow (natural flow) that does not generate pack pressure. In addition, the mold is opened by filling the resin amount to which the amount of cooling solidification shrinkage of the resin is added, and extending the tie bar to the mold opening amount corresponding to the amount of cooling solidification shrinkage of the resin by the filled resin pressure. Even if injection filling is completed by setting the allowable mold clamping force, the mold is almost completely filled with resin (just pack), and the stretched tie bar has elastic flexibility. , And the elastic recovery force of the tie bar constantly adds a compression action corresponding to the cooling, solidification, and shrinkage behavior of the resin, so that the flow mark due to the discontinuity of the resin flow velocity in the mold even when switching the mold clamping pressure increase. And is not affected at all by the occurrence of defects. Therefore, complicated and sophisticated timing control for starting the mold clamping pressure increase, which has been conventionally performed, becomes unnecessary. Further, since the mold clamping force is detected by the mold clamping force detector incorporated in the tie bar, a highly accurate mold clamping force can be directly detected without any influence from the setting of the mold thickness and the die height adjustment. In addition, by performing the injection filling process in parallel with the mold clamping force setting operation, and by enabling high-speed operation until the mold is touched for most of the mold clamping operation time, the molding cycle can be shortened. As a result, productivity is remarkably improved.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The embodiments of the present invention will be described below in detail with reference to the drawings. 1 to 3 relate to the present invention, FIG. 1 is an overall configuration diagram of an injection molding apparatus, FIG. 2 is an explanatory view showing a correlation between a set mold clamping force and a tie bar elongation amount, and FIG. FIG. 6 is a state explanatory diagram for explaining a state. The upper half of the injection molding apparatus in FIG. 1 shows a state at the time of setting a mold clamping force before injection filling, and the lower half shows a state of mold clamping completed in a compression step.

As shown in FIG. 1, an injection molding apparatus 100 for performing injection compression molding is roughly composed of a mold clamping device 20, an injection device 40, and a control unit 60.
Are the link housing 1, fixed plate 2, movable plate 3, mold clamping cylinder 8, toggle mechanism 6 (toggle link 6a, mid link 6b, crosshead link 6c), crosshead 7, piston rod 9, guide rod 10, gold It comprises a mold 4 (movable mold 4a, fixed mold 4b), cavity 5, tie bar 11, and the like.

Next, the injection device 40 will be described. In the injection device 40 in this embodiment, a screw 42 is provided in a barrel 41, and a resin material in a hopper 43 is heated and compressed in a supply zone and a compression zone, melted and weighed in a measurement zone, and passed through an injection zone to a nozzle 44.
It is configured to be injected into the interior. A heater for externally heating the resin material is provided on the outer peripheral surface of the barrel 41, and the resin material is sent forward by the rotation of the screw 42. Reference numeral 46 denotes an injection cylinder, and 47 denotes a forward / reverse rotation motor.
, So that the screw 42 rotates forward and backward.

Next, the control unit 60 will be described. The control unit 60 includes an injection filling amount setting unit 61 and an injection pressure setting unit 6
2. Injection controller 63, hydraulic control valve 64, pressure sensor 6
5. Hydraulic control valve 67, hydraulic supply sources 68a, 68b, injection filling completion detecting section 69, timer 70, time setting section 71, comparison control section 72, mold clamping control section 73, mold clamping cylinder stroke sensor 74, mold clamping force Detector 75, mold clamping force setting means 7
6. It comprises a mold touch point setting unit 78 and the like. The injection filling amount setting means 61 and the injection pressure setting means 62 are connected to the injection control section 63, and the injection control section 63 controls the operation of the hydraulic control valve 64 for controlling the operation of the injection cylinder 46 and the operation of the forward / reverse rotation motor 47. Connected to control devices (not shown). The operating oil pressure in the injection cylinder 46 is detected by the pressure sensor 65, and the injection filling completion detection unit 6
9, a position information detected by a mold clamping cylinder stroke sensor 74 and a mold clamping force detecting unit 75 which are sent to the mold clamping control unit 73 via the timer 70 and the comparison control unit 72.
Is transmitted to the mold clamping force setting means 76, an operation signal is transmitted to the mold clamping control unit 73, and an operation command is given to the hydraulic control valve 67 for controlling the mold clamping cylinder 8. Has become. The clamping force detecting unit 75
Is incorporated in the tie bar 11, for example, a load meter is used. The mold clamping cylinder stroke sensor 74 is attached to the piston rod 9 of the mold clamping cylinder 8, and employs an encoder and a linear scale. Also, a line is provided so that touch information in the mold touch point setting unit 78 is immediately sent to the mold clamping control unit 73 and the injection control unit 63.

[0011] The injection molding apparatus 100 configured as described above.
The operation procedure of the injection compression molding method in the above will be described below.

First, an injection filling amount setting means 61 is defined as a resin amount obtained by adding a cooling solidification shrinkage amount of a resin calculated according to resin physical properties to a cavity volume defined by the fixed mold 4b and the movable mold 4a. And the injection pressure setting means 62 sets an injection pressure condition with the best injection efficiency from an injection filling pressure range in which the cavity 5 can be filled and does not generate burrs as an injection pressure value. At the same time, the tie bar 11 is subjected to the injection filling behavior from the set measurement value and injection pressure value, the cavity volume and the projected area of the cavity to the mold opening amount corresponding to the amount of cooling, solidification and shrinkage of the resin when the injection filling is completed.
The mold clamping force setting means 76 sets a mold clamping force that allows the mold to open due to the extension.

In this case, the toggle mechanism 6 is not fully extended, and the relationship between the tie bar extension amount and the set mold clamping force will be described in detail with reference to FIG. That is, the principle of generating the mold clamping force in the toggle mold clamping device 20 is that the movable mechanism 3 is advanced by driving the toggle mechanism 6 and the movable mold 4a and the fixed mold 4b are touched (at this time, the toggle mechanism 6 is not stretched yet, Ko value), and the movable platen 3 is further pressed toward the fixed platen 2 to extend the diver 11, thereby generating a mold clamping force (moving the mold clamping cylinder 8 forward). When the toggle mechanism 6 is fully extended, the mold clamping force has a maximum value (however, when the die height is adjusted to a mold clamping force value according to the cavity projection area according to the mold size to protect the mold, a Kmax value). At this time, the tie bar 11
Is extended to the maximum value (△ lmax value).

When the injection compression molding is performed by utilizing the extension of the tie bar 11, the maximum allowable extension amount (△ lmax value) of the tie bar 11 is in a range where the mold opening amount can be adjusted by the injection filling pressure. Here, assuming that the mold opening amount corresponding to the amount of resin solidification shrinkage at the time of completion of injection filling is an S value, the mold clamping force is set so that the mold clamping force Ks becomes smaller than the maximum mold clamping force Kmax. As a result, the mold opening amount S can be secured. Even in this state, since the toggle mechanism 6 is in a state very close to the most extended state (linear state), the movable platen 3 does not retreat due to the injection filling pressure.

Further, a state in which the molten resin is almost completely filled in the mold at the completion of the injection filling (just pack) is defined as an appropriate mold opening amount. By doing this, there is no change in the flow of the resin when moving from the completion of the injection filling to the compression process, so there are no defects such as flow marks caused by this, and the injection process and the start of mold clamping pressure increase are linked. You don't have to.

The mold opening behavior accompanying the injection filling is a result given by the extension of the tie bar 11, and the set mold clamping force is the same as the extension of the tie bar 11, but is actually applied to the mold. Since the mold clamping force showed a tendency to increase, it was found that the relationship between the injection filling pressure, the mold opening amount, and the mold clamping force acted in a direction to automatically balance. That is, in the toggle type mold clamping device 20, when setting the appropriate mold opening amount, even if the condition of the appropriate mold clamping force value is set somewhat rough, the direct pressure type is achieved by the automatic balance correction of the mold clamping force due to the extension of the tie bar 11. Compared to the case of the mold clamping device,
An advantage that molding control becomes easy was also obtained.

When the initial setting is completed as described above,
Next, as shown in FIG. 3, the molding operation starts. (1) The mold clamping control unit 73 controls the operation of the mold clamping cylinder 8 to perform mold clamping (primary pressure) based on the mold clamping force set value set by the mold clamping force setting means 76. (2) The detection of the mold clamping force during the mold clamping operation is performed by the mold clamping force detector 75 incorporated in the tie bar 11. The advantage is that the tie bar 1 which is the principle of generating the mold clamping force of the toggle mechanism 6
Since the elongation (stress) behavior of No. 1 is directly measured, the measurement accuracy is the highest. There is no disadvantage in the conventional method of calculating based on the geometric relationship of the toggle mechanism 6 (accumulation of operation programs close to infinity, low accuracy due to operation estimation). Since the position is irrelevant to the mold mounting portion, the handleability is extremely good.

(3) In order to detect the touch state of the mold during the mold clamping operation by the mold clamping force detecting unit 75 and use it as a reference for the subsequent molding operation, the mold clamping cylinder stroke is reset to zero and the mold clamping origin is set. I do. (4) The stroke of the mold clamping cylinder 8 at the time when the set mold clamping force is reached is detected by the mold clamping cylinder stroke sensor 74, and thereafter control is performed based on the detected signal value. That is,
The mold cylinder pressure is controlled so as to keep the detection signal value. (Mold clamping cylinder position holding control). Here, the characteristics of the toggle mechanism 6 (the position variation of the movable platen is 1 / several tens mm or less even if the mold clamping cylinder stroke varies by about 1 mm,
Therefore, the influence on the mold clamping force is extremely small. In fact, the mold clamping cylinder stroke can be held with an accuracy of 1 mm to 1/10 mm. ) And the above-described automatic balance operation of the interrelationship between the injection filling pressure, the mold opening amount and the mold clamping force, makes it possible to easily control the mold clamping force with extremely high precision.

(5) The above (2) to (4) need only be set once before the molding operation unless the mold and the set value of the mold clamping force in the compression step (by adjusting the die height) are changed. The actual molding operation is performed based on the previously set mold touch state (origin) and the stroke position of the mold clamping cylinder 8 corresponding to the set mold clamping force. After that, the mold clamping cylinder 8 is advanced at a low speed to the mold clamping force setting position, and the injection filling operation is performed in parallel. Note that the mold clamping force setting operation needs to be completed before the injection filling is completed. (6) After the mold touch state, the mold touch point setting unit 78 transmits a mold clamping force setting start signal to the mold clamping control unit 73 and transmits an injection start signal to the injection control unit 63. Here, the injection filling operation is performed by the injection control section 63 based on the resin metering value set by the injection filling amount setting means 61 and the injection pressure setting means 62 and the injection filling pressure based on the set value of the injection filling pressure. Perform filling. That is, in the early stage of injection, the flow resistance in the cavity 5 is small, so that high-speed filling is performed. In the late stage of injection, the filling speed is naturally reduced with an increase in the flow resistance in the cavity 5, resulting in a continuous speed gradient. And
In addition, an ideal natural filling flow (natural flow) that does not generate a pack pressure is obtained. Further, since the mold clamping (primary pressure) is set in parallel with the start of injection, the mold clamping force applied to the mold gradually increases, so that the above-mentioned natural flow is promoted. Further, in the present embodiment, during the injection filling step, the injection control is performed such that the screw 42 is cut off so as not to leave a so-called cushion amount until the screw 42 reaches the forward limit by the pressure control of the injection cylinder 46. By doing so, the detection for confirming the completion of injection filling described later is extremely easy and accurate, and the weighing and injection filling control are also simplified.

(7) After the injection filling is completed (at this point, the mold clamping force setting operation has already been completed and kept at the set mold clamping force), the compression step is performed on the mold clamping side. The mold is opened by the extension of the tie bar 11 in response to the injection filling, and the mold opening amount becomes maximum after the injection filling is completed. Here, after the injection filling is completed, the molten resin in the mold is in a just-packed state, the stretching behavior of the tie bar 11 acts elastically, and the compression according to the cooling solidification shrinkage of the resin is added by the elastic recovery force. As a result, no defect such as a flow mark occurs at the time of switching from the injection process to the compression process. If the operating oil pressure in the injection cylinder 46 is increased with the compression (the injection cylinder does not advance), the resin is filled in the passage from the nozzle 44 to the cavity 5, so that the resin in the mold is filled. Backflow can be completely prevented. (8) The detection of the completion of the injection filling is obtained by a change in the operating oil pressure value in the injection cylinder 46 or a change in the forward movement (injection speed) of the injection piston 48 in the above-described cutoff state. That is, since the working oil pressure value in the injection cylinder 46 is controlled to be constant along with the forward movement of the screw 42 so that the injection filling pressure is constant from the start of the injection filling to just before the injection is completed, When the screw 42 reaches the forward limit, the forward movement of the screw 42 stops, and the operating oil pressure value in the injection cylinder 46 temporarily and rapidly rises. Therefore, by detecting the operating oil pressure value in the injection cylinder 46, the completion of the injection filling can be accurately detected. However, the present invention is not limited to this, and when the forward movement of the screw 42 or the forward movement of the injection piston 48 is stopped, the completion of the injection filling may be detected. Furthermore, it is also possible to use a method for confirming and detecting the completion of injection filling as described above in combination.

(9) When the completion of the injection and filling is detected by the injection and filling completion detecting section 69, the timer 70 is started to control the compression process. Here, the time at which the mold clamping pressure increase (secondary pressure) start time, the measurement start time, and the holding pressure cooling time are input to the time setting unit 71 in advance. The start of metering is set on the basis of the time for sealing the gate, and in a molding machine incorporating a shut-off valve, the time is set based on the completion time of the closing operation of the shut-off valve. The holding pressure cooling time is calculated as the compression solidification time of the resin based on the resin temperature, the mold cooling capacity, the shape of the molded product, and the like, and set as the compression completion time. By setting the mold clamping pressure increase start time to be the same as the measurement start time setting, it is possible to prevent the resin from flowing back from the mold cavity 5 to the injection side due to the mold clamping pressure increase. Here, a slight time lag occurs from the completion of the injection filling to the start of the mold clamping pressure increase. However, the compressive action of the elastic recovery force of the tie bar 11 due to the continuation of the mold clamping primary pressure is added in accordance with the cooling solidification shrinkage of the resin. Therefore, there is no defect caused by the time lag. (10) Timeout signal of timer 70 and time setting section 7
The set value of 1 is compared by the comparison control unit 72, and when it is found that each set value has been reached, a measurement start signal is output to the injection control unit 63, and the mold clamping pressure increasing start time and the compression completion signal are compared with the mold clamping signal. After the output to the control section 73 and the removal of the product following the mold opening, the next molding operation is started. (11) The value of the clamping force (secondary clamping pressure) after increasing the clamping pressure is added for the purpose of improving the transferability of the molded product. Within the mold clamping pressure range between the clamping pressures, for example, the transferability of the molded article after molding can be evaluated to determine the required minimum mold clamping force value by the mold clamping force setting means 76. Further, it is also possible to make the set values of the secondary mold clamping force and the primary mold clamping force the same, and in this case, the compression step is added only by the elastic recovery force of the tie bar 11, especially the molded product Is expected to be highly effective in reducing the residual strain of the molded article and obtaining a high-quality molded article with extremely little deformation.

[0022]

As is apparent from the above description, in the present invention, the injection filling step and the compression step need only be a simple control method of controlling the injection pressure and the mold clamping force, so that the operability is extremely easy. Becomes In addition, by using injection pressure control that allows injection filling,
The ideal injection filling control that has a continuous speed gradient according to the product shape, does not generate pack pressure, and enables short-time filling can be set very easily and automatically, making control operability extremely easy. is there. Even when the injection filling is completed, the molten resin is in a just-packed state, so that there is no defect such as a flow mark caused by the discontinuity of the resin flow. Since timing control is not required, operability of control can be further simplified. Injection filling control is injection pressure control and filling is performed without leaving a cushion amount, so that injection filling completion detection can be detected easily and accurately, and mold clamping start control can be simplified. The control of the compression process and the start of weighing can be performed by simple control using a timer, and a high-quality molded product can be obtained by an extremely easy operation. Since the mold clamping force is detected directly at the tie bar, which is the principle of the mold clamping force of the toggle mold clamping mechanism, the measurement accuracy is extremely high, and the mold clamping force can be set under any conditions. Because it can be handled, the operability and accuracy of the control are extremely good. Since the injection filling process is performed in parallel with the mold clamping force setting operation and the mold clamping operation up to the touch state of the mold is performed at a high speed, the molding cycle can be shortened, and the productivity is significantly improved.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of an injection molding machine according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a correlation between a set mold clamping force and a tie bar elongation amount according to the embodiment of the present invention.

FIG. 3 is an explanatory view of a state of an injection compression molding method according to an embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Link housing 2 Fixed board 3 Movable board 4 Mold 4a Movable mold 4b Fixed mold 5 Cavity 6 Toggle mechanism 7 Crosshead 8 Mold clamping cylinder 9 Piston rod 10 Guide rod 11 Tie bar 20 Mold clamping device (Toggle type clamping device) 40) Injection device 41 Barrel 42 Screw 43 Hopper 44 Nozzle 46 Injection cylinder 47 Forward / reverse rotation motor 48 Piston 60 Control unit 61 Injection filling amount setting means 62 Injection pressure setting means 63 Injection control unit 64 Hydraulic control valve 65 Pressure sensor 67 Hydraulic control Valves 68a, 68b Hydraulic pressure supply source 69 Injection and filling completion detection unit 70 Timer 71 Time setting unit 72 Comparison control unit 73 Mold clamping control unit 74 Mold clamping cylinder stroke sensor 75 Mold clamping force detection unit 76 Mold clamping force setting means 78 Mold touch Point setting unit 100 Injection molding device

Claims (3)

(57) [Claims] 1. An injection molding apparatus which performs mold clamping by using a toggle mechanism, calculates a cooling solidification shrinkage amount of a resin in advance at an injection mechanism side in an injection filling step, and adds the shrinkage amount to a resin amount. The injection pressure is controlled by the injection pressure which can be filled in the mold cavity, and the mold clamping mechanism side is controlled by the pressure of the resin previously filled in the mold cavity to a mold opening amount corresponding to the amount of the resin which is cooled, solidified and contracted. A mold clamping force was set to allow the mold to open by the extension of the tie bar, and the movable plate was advanced through the toggle mechanism, and both molds were touched in a state where the toggle mechanism was not fully extended. The toggle mechanism is extended from the state to the set value of the mold clamping force.In the injection filling step, the injection filling operation is performed during the mold clamping force setting operation of the mold clamping mechanism, and after the injection filling is completed, the injection mechanism is retracted during the injection filling operation. An injection compression molding method in which the movable platen is advanced to increase the mold clamping force. 2. Using a mold clamping force detector incorporated in a tie bar in advance, detecting a state in which both molds are touched, setting the stroke of a mold clamping cylinder connected to a toggle mechanism to an origin, and setting the stroke to a set mold clamping force. 2. The injection compression molding method according to claim 1, wherein the hydraulic pressure of the mold clamping cylinder is controlled so as to maintain the stroke position of the mold clamping cylinder that has reached the set mold clamping force after extending the toggle mechanism until the toggle mechanism reaches the set position. 3. An injection control unit which comprises an injection filling amount setting means and an injection pressure setting means, and performs injection filling based on the both setting means, and a mold opening amount corresponding to a cooling solidification shrinkage amount of the resin by the injection filling. A mold clamping force setting means for setting a mold clamping force that allows the mold to open by extending the tie bar, a mold clamping cylinder stroke sensor for detecting a stroke of the mold clamping cylinder, and a mold clamping process incorporated in the tie bar. A mold clamping force detecting section for detecting the mold clamping force, a mold touch point setting section for setting a mold touch point based on a detection signal of the mold clamping force detecting section, and setting of the mold clamping force setting means. A mold clamping control unit for performing a mold clamping by controlling a stroke of a mold clamping cylinder connected to a toggle mechanism by comparing a value with a detection signal of the mold clamping cylinder stroke sensor, and setting the mold touch point. Department An injection filling completion detection unit that transmits a mold clamping force setting start signal to the mold clamping control unit after the origin setting is completed and transmits an injection start signal to the injection control unit, and transmits an injection filling completion signal. An injection compression molding apparatus comprising a comparison control unit for transmitting a mold clamping pressure increasing signal to the mold clamping control unit based on a detection signal from the injection filling completion detecting unit.