JP2006035845A - Injection molding machine and resin material recovery method in injection molding machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an injection molding machine capable of efficiently discharging the resin material in a material supply part. <P>SOLUTION: In the injection molding machine S equipped with a mold 30, a mold clamping means 80, an injection means 10 and a vacuum discharge means 90, the resin material is supplied into a cylinder 11 through the material holding part 27 of the material supply part 20 to be injected in the cavity 30a of the mold 30. One end of piping 29 for discharging the resin material is allowed to communicate with the material holding part 27 and the other end thereof is connected to the vacuum discharge means 90. A material recovery pipe 29e is detachably provided on the way of the piping 29 and a filter 29f is provided on the downstream side of the material recovery pipe 29e. When the vacuum discharge means 90 is operated, the resin material in the material holding part 27 is allowed to flow out toward the piping 29 by the suction force of the vacuum discharge means 90 to flow in the material recovery pipe 29e and intercepted by the filter 29f to be stored in the material recovery pipe 29e. The material recovery pipe 29e is detached from piping 28 to discharge the resin material to the outside. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an injection molding device, and in particular, an injection molding device capable of easily recovering a resin material remaining in a material supply unit while the cavity and the resin material are held in a vacuum state, and The present invention relates to a resin material recovery method in an injection molding apparatus.

2. Description of the Related Art Conventionally, there is known an injection molding apparatus that can evacuate a cavity after clamping a mold (see, for example, Patent Document 1).
In the injection molding apparatus of Patent Document 1, a material supply cylinder for supplying a solid resin material is connected to an upper portion of a plasticizing cylinder for superheat fluidizing the solid resin material. The material supply cylinder is provided with a suction pump connected to a vacuum pump, and the inside of the material supply cylinder is evacuated by the suction pump. Further, the plasticizing cylinder is also evacuated.

JP 2002-154136 A (page 4-5, FIG. 1)

  The material supply cylinder of Patent Document 1 is not particularly provided with a device for discharging the solid resin material once put into the material passage of the material supply cylinder to the outside. Conventionally, in order to discharge the resin material once charged from the material supply cylinder, the material supply cylinder is shifted from the plasticizing cylinder or removed from the plasticizing cylinder. The resin material was discharged by communicating the bottom with the outside. Further, the resin was repeatedly injected until there was no remaining resin material.

  However, in order to discharge the resin material, removing the material supply cylinder from the plasticizing cylinder or repeatedly injecting the resin each time is a troublesome operation. Moreover, the operation | work which removes the material supply cylinder attached above the plasticizing cylinder was an operation | work which requires safety management. In addition, if the bottom of the material supply tube is communicated with the outside, the resin material spills onto the floor surface, which takes time for the recovery operation, and thus there is a problem that the recovery operation cannot be performed efficiently.

  The present invention has been made in view of the above problems, and an object of the present invention is to efficiently and easily discharge unused solid resin material remaining in a material supply unit of an injection molding apparatus. Another object of the present invention is to provide an injection molding apparatus using a vacuum molding die that does not require time and effort for cleaning the inside of the material supply cylinder and replacing the solid resin material, and a resin material recovery method in the injection molding apparatus.

  According to the injection molding apparatus of the present invention, the object is to provide a mold having a cavity formed by a fixed side mold and a movable side mold, mold clamping means capable of clamping the mold, and a resin material. An injection molding apparatus comprising: an injection unit that melts and injects molten resin into the cavity; and an injection unit that includes a material supply unit that supplies a resin material to the injection unit, wherein the material supply unit includes a resin A discharge portion for discharging the material, the discharge portion communicating with the material supply portion, a suction means for sucking the resin material together with air through the discharge passage, and communicating with the discharge passage; And the recovery means for the sucked resin material to flow into the inside, and the recovery means is configured to be able to discharge the flow-in resin material to the outside.

As described above, in the present invention, the material supply unit for supplying the resin material to the injection unit for melting the resin material and injecting the molten resin into the cavity is provided with a discharge unit for discharging the input resin material. The discharge portion includes a discharge passage having one end communicating with the material supply portion, and suction means for sucking the resin material together with air from the other end of the discharge passage. Accordingly, the resin material remaining in the material supply unit can be sucked into the discharge passage.
Further, in the present invention, a recovery means for allowing the sucked resin material to flow in is communicated with the discharge passage, and the recovery means is configured to be able to discharge the inflowed resin material to the outside. Therefore, the sucked resin material can be flown into the collection means and discharged to the outside.

  In the present invention, since the resin material can be sucked into the collecting means from the material supply section through the discharge passage and the resin material can be discharged from the collecting means to the outside, the remaining resin can be discharged as in the prior art. There is no need to repeat the injection until there is no more material. Further, it is not necessary to remove the material supply unit from the injection means in order to discharge the resin material. Therefore, it is possible to easily and safely collect the resin material without requiring labor.

In the present invention, it further includes a vacuum evacuation unit for evacuating the cavity, and the material supply unit is connected to the vacuum evacuation unit, and the injection is performed while the resin material is held under vacuum. It can be possible to supply to the part.
If comprised in this way, an injection molding can be performed by evacuating a cavity by a vacuum exhaust means. The material supply unit can supply the resin material to the injection unit in a state where the resin material is held under vacuum. Accordingly, since the resin material is melted in the injection portion while being kept in a vacuum state, the molten resin injected into the mold can be made free of gas and moisture, and the quality of the molded product can be improved. It becomes possible to improve.

  In the present invention, it is preferable that the evacuation unit functions as the suction unit. With this configuration, it is not necessary to provide a suction unit separately from the vacuum exhaust unit that evacuates the cavity, so that the configuration of the apparatus can be simplified.

In the present invention, the recovery means is a tubular member provided with a filter member at one end, and is attached in the middle of the discharge passage so that the end on the filter member side is positioned on the suction means side. It can be configured.
If comprised in this way, the resin material attracted | sucked with air from the material supply part side will flow in the inside of the tubular member provided with the filter member at the suction means side. The resin material sucked together with the air is dammed inside the tubular member by the filter member, and the resin material can be collected inside. As described above, the resin material can be collected with a simple configuration by using the tubular member and the filter member which are easily attached in the middle of the passage.

  Moreover, in this invention, the said tubular member can be set as the structure by which the edge part by the side of the said material supply part can be attached or detached with the said discharge channel. If it does in this way, the internal space of a tubular member can be connected with the exterior by removing the edge part by the side of the material supply part of a tubular member from a discharge passage. Therefore, the resin material sucked from the material supply section through the discharge passage and blocked by the filter member inside the tubular member can be discharged to the outside. In this case, it is not necessary to separately provide a discharge hole for discharging the resin in the tubular member, and the resin can be discharged from the tubular member to the outside with a simple configuration.

  Further, according to the resin material recovery method in the injection molding apparatus of the present invention, the problem is that a mold having a cavity formed by a fixed mold and a movable mold, and a mold capable of clamping the mold. Injecting means having a fastening means, an injection portion that melts a resin material and injects the molten resin into the cavity, a material supply portion that supplies the resin material to the injection portion, and vacuum exhaust for evacuating the cavity A resin material recovery method for discharging the resin material charged into the material supply unit to the outside, wherein the material supply unit is evacuated to hold the resin material under vacuum Supplying the injection means in a state where the material supply unit is in communication with outside air, and sucking the resin material together with air through the discharge passage communicated with the material supply unit. Steps for flowing the inside of the collecting means mounted in the middle of the step of discharging a resin material to the outside from the recovery means, it is solved by performing.

  As described above, in the present invention, the resin material can be sucked from the material supply unit by the suction means, flowed into the recovery means from the discharge passage, and discharged to the outside from the recovery means. There is no need to repeat the injection until there is no more material. Further, it is not necessary to remove the material supply unit from the injection means in order to discharge the resin material. Therefore, it is possible to easily and safely collect the resin material without requiring labor.

According to the injection molding apparatus and the resin material recovery method in the injection molding apparatus of the present invention, the resin material remaining in the material supply part is sucked from the material supply part by the suction means and flows out to the discharge passage, and is recovered from the discharge passage. And can be discharged from the collecting means to the outside.
Therefore, unlike the prior art, there is no need to repeat injection until there is no remaining resin material. Further, it is not necessary to remove the material supply unit from the injection means in order to discharge the resin material. Thereby, the collection operation | work of a resin material can be performed easily and safely, without requiring an effort.

  Further, in the present invention, the resin material sucked into the discharge passage from the material supply section is caused to flow into a tubular member attached in the middle of the discharge passage and dammed inside by the filter member, so that the resin material can be recovered with a simple configuration. can do. Further, by removing the end of the tubular member on the material supply portion side from the discharge passage, the internal space of the tubular member can be communicated with the outside, and the resin material collected in the tubular member can be discharged to the outside. There is no need to separately provide a discharge hole or the like for discharging the resin to the member, and the resin can be discharged from the tubular member to the outside with a simple configuration.

  Further, in the present invention, the cavity can be evacuated by vacuum evacuation means to perform injection molding. In addition, since the resin material is melted in the injection part while being kept in a vacuum state, the molten resin injected into the mold can be made free of gas and moisture, and the quality of the molded product can be improved. Is possible.

  Further, in the present invention, the resin material is sucked by the vacuum evacuation means, and it is not necessary to provide the suction means separately from the vacuum evacuation means for evacuating the cavity, thereby simplifying the configuration of the apparatus. Can do.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. It should be noted that members, arrangements, and the like described below do not limit the present invention, and it goes without saying that various modifications can be made in accordance with the spirit of the present invention.

1 to 10 relate to an embodiment of the present invention, FIG. 1 is an explanatory view of an injection molding apparatus, FIG. 2 is an explanatory view of a mold, FIG. 3 is an explanatory view of a control means, and FIGS. 6 is an explanatory diagram of a mold vacuum valve, FIG. 7 is an explanatory diagram of a material supply unit, FIG. 8 is an explanatory diagram of a vent cover of the material supply unit, FIG. 9 is a timing chart of the material supply unit, and FIG. It is a timing chart of a valve.
FIG. 11 is an explanatory view of an injection molding apparatus according to another embodiment of the present invention.

First, the overall configuration of the injection molding apparatus S of the present embodiment will be described.
FIG. 1 is an explanatory sectional view of an injection molding apparatus S of the present invention. As shown in FIG. 1, the injection molding apparatus S includes an injection unit 10, a mold 30, a mold clamping unit 80, a vacuum exhaust unit 90, and a control unit 100 as main components. The injection unit 10 and the mold clamping unit 80 are mounted on the gantry 1, and the mold 30 is mounted on the mold clamping unit 80.

  The injection means 10 of this example is a screw-in-line type injection machine, and includes a cylinder 11, a nozzle 13, a drive unit 14, and a material supply unit 20 for supplying resin material into the cylinder 11. Configured. The cylinder 11, the nozzle 13, and the drive unit 14 correspond to an injection unit.

  The drive unit 14 includes a rotation drive unit 14a including a motor and a speed reduction mechanism that rotate the screw 12 in the cylinder 11, an injection cylinder device 14b that extrudes the screw 12 and injects molten resin in the cylinder 11 into the mold 30, and a cylinder. 11 is provided with a shift cylinder that moves the nozzle 11 in the left-right direction to bring the nozzle 13 into contact with or retract from the sprue.

  In the cylinder 11 of this example, a vacuum seal 11a is disposed at a position behind the opening for communicating the material supply unit 20 and the cylinder 11 (right side in the figure), and a screw 12 is inserted into the vacuum seal 11a. It is slidable. The vacuum seal 11 a seals the inside of the cylinder 11 and the drive unit 14.

  The cylinder 11 is heated by a band heater 15. The resin material is supplied into the cylinder 11 through the material supply unit 20, plasticized and kneaded by the screw 12 that is rotationally driven by the rotation driving unit 14 a, and pushed forward. When the injection cylinder device 14b is operated in this state, the screw 12 is pushed out to the mold 30 side, and the front molten resin in the cylinder 11 is injected into the cavity 30a in the mold 30 through the nozzle 13.

  In addition, although the injection means 10 of this example is a screw-in-line type, it is not limited to this, and may be a plunger type or a pre-plastic type.

  As shown in FIGS. 1 and 2, the mold 30 is disposed relative to the fixed side mounting plate 33 </ b> A, the fixed side mold 31 attached to the fixed side mounting plate 33 </ b> A, and the fixed side mold 31. The movable mold 32, the back plate 34 that supports the movable mold 32 from the back side, the movable mounting plate 37A connected to the back plate 34 via the spacer block, the back plate 34, and the movable mounting plate. The main components are an ejector plate 35 movably disposed between 37A and an ejector pin 36A having a base fixed to the ejector plate 35. And the cavity 30a for shape | molding a molded article is formed by clamping the fixed side metal mold | die 31 and the movable side metal mold | die 32. FIG.

  The fixed-side mold 31 incorporates mold vacuum valves 40 and 50 serving as exhaust parts to be described later. The fixed side mold 31 is provided with a recess 31e on the side surface in contact with the fixed side mounting plate 33A, and the mold vacuum valve 40 is attached to the recess 31e. This mold vacuum valve 40 is configured to be able to switch between communicating the gate 31d of the fixed mold 31 to the nozzle 13 side or communicating to the vacuum exhaust means 90 side. The mold vacuum valve 50 is disposed in the recess 32e and the recess 32f formed in the movable mold 32, and is configured to be able to switch whether the cavity 30a communicates with the evacuation means 90 side. Has been.

  Further, an electromagnetic valve 59b is provided in a pipe 59 extending from the mold vacuum valves 40, 50 to the vacuum tank 92 side of the vacuum exhaust means 90. The electromagnetic valve 59b is connected to the mold vacuum valves 40, 50 with a vacuum. The exhaust means 90 can be communicated or closed. A pipe 59 between the electromagnetic valve 59b and the mold vacuum valves 40 and 50 is provided with a vacuum sensor 59a and a digital vacuum meter 59c. The pressure in the cavity 30a communicated with the pipe 59 and the pipe 59 is measured. Measuring. The vacuum sensor 59a displays the internal atmospheric pressure on the display unit. The vacuum meter 59c sends a detection signal representing the internal atmospheric pressure value to the control means 100, and the control means 100 uses this detection signal for control and display.

  The mold clamping means 80 includes a fixed die plate 81 fixed to the end of the tie bar 83, a mold clamping mechanism 86, and a movable die plate 82 that can move forward and backward with respect to the fixed die plate 81 by the mold clamping mechanism 86. And a drive unit 87 for driving the mold clamping mechanism 86 and the like.

The fixed side die plate 81 supports the fixed side mounting plate 33A, and the movable side die plate 82 supports the movable side mounting plate 37A.
The mold clamping mechanism 86 is configured by a link mechanism or the like, and is configured so that the position of the movable mold 32 can be adjusted by being driven by the drive unit 87.

  The mold clamping means 80 is provided with a position detection switch 88 for detecting the position of the movable mold 32. The position detection switch 88 detects that the movable mold 32 is in the mold clamping position. The position detection signal is sent to the control means 100.

  Further, the drive unit 87 can move the ejector plate 35 forward and backward toward the movable mold 32 side. After the mold opening, when the drive unit 87 is driven and the ejector plate 35 advances to the movable mold 32 side, the molded product is removed from the mold surface of the movable mold 32 by the ejector pins 36A.

The vacuum exhaust means 90 is for evacuating the inside of the cavity 30a of the mold 30 and the material supply unit 20, and includes a vacuum pump 91 and a vacuum tank 92 as main components.
The pipe from the vacuum tank 92 branches into two pipes (28, 59) that go to the electromagnetic valve 28a and the electromagnetic valve 59b on the way. A vacuum sensor 90a and a digital vacuum meter 90b are attached to the piping between the vacuum tank 92, the electromagnetic valve 28a, and the electromagnetic valve 59b. The vacuum sensor 90a displays the internal atmospheric pressure on the display unit. The vacuum meter 90 b sends a detection signal obtained by measuring the internal atmospheric pressure to the control means 100. The control means 100 uses this detection signal for control and display.

  The vacuum pump 91 always exhausts the vacuum tank 92 so as to maintain a predetermined degree of vacuum. That is, the control means 100 monitors the degree of vacuum in the vacuum tank 92 based on the detection signal received from the vacuum meter 90b, and when it is determined that the vacuum tank 92 has become greater than a predetermined atmospheric pressure value, the vacuum pump 91 To evacuate the vacuum tank 92 to a predetermined degree of vacuum.

  Further, the control means 100 controls the electromagnetic valves 28a, 28b, 59b so as to exhaust the interior of the cavity 30a and the material supply unit 20 at a predetermined timing.

  As shown in FIG. 3, the control unit 100 includes a control unit 101, a display unit 102, and an operation unit 103 as main components. The control unit 101 stores a control program and receives an operation signal from the operation unit 103, a position signal from a solenoid valve, a sensor, a limit switch, a vacuum meter, a detection signal, and the like, The operation signal is sent to etc. The display unit 102 displays the operating status of each device such as the open / close status of each electromagnetic valve and the atmospheric pressure value measured by a vacuum meter.

  In the movable side mold 32 of this example, a convex mold seal member made of silicon rubber is disposed so as to surround the cavity 30a, and the fixed side mold 31 has a mold seal member at the time of mold clamping. A mold seal groove into which is inserted is formed. The mold 30 of this example is configured such that when the mold is clamped, the mold seal member and the mold seal groove are engaged to seal the cavity 30a.

  A sliding hole (through hole) is formed in the movable mold 32 so that the cavity 30a communicates with the outside (back plate 34) side, and an ejector as a sliding member is formed in the sliding hole. The pin 36A can slide forward and backward. A seal member that seals between the cavity 30a and the outside is also disposed in the sliding hole. The ejector pin 36A slides with this seal member.

(Cavity evacuation structure)
Next, the mold vacuum valve 40 of this example is demonstrated based on FIG.
FIG. 4 is a cross-sectional explanatory view of the mold vacuum valve 40 as viewed from the nozzle 13 side.

  The mold vacuum valve 40 of this example includes a main body portion 40a, a valve body 47 that slides within the main body portion 40a, a coil spring 48 as an urging means for urging the valve body 47, and a main body portion 40a. Are connected to the end portions of the operating hose 43a and the exhaust hose 44a. The connecting portion 42 communicates with the operation hose 43a and the exhaust hose 44a, and a pipe 59 is connected to the outside.

  A sprue 41 is formed in the main body portion 40a so as to penetrate the main body portion 40a. A bottomed actuation hole 43 is formed in a direction substantially orthogonal to the sprue 41 from the side surface of the main body 40a. The operating hole 43 communicates with the sprue 41 through an exhaust hole 41 a formed on the side surface of the sprue 41. An operation hose 43 a is connected to the operation hole 43.

  Further, a bottomed exhaust hole 44 is formed in the main body portion 40 a in parallel with the operation hole 43, and the exhaust hole 44 and the operation hole 43 communicate with each other through a communication hole 45. . The communication hole 45 is formed on the side close to the sprue 41 (that is, the side close to the bottom). An exhaust hose 44 a is connected to the exhaust hole 44. The exhaust hole 44 is formed to have a smaller diameter than the operation hole 43.

  The valve body 47 is disposed in the operating hole 43, and includes a disc portion 47b, a cylindrical cap portion 47a formed so as to penetrate the disc portion 47b, and a cap portion 47a from the rear side of the cap portion 47a. The sliding portion 47c is formed so as to extend in the length direction.

  The cap part 47a is a member for closing the exhaust hole 41a. The operation hole 43 has a tapered shape at a portion communicating with the exhaust hole 41a, and the tip portion 47aa of the cap portion 47a is also tapered in accordance with the taper portion 43c. The cap portion 47a is urged toward the exhaust hole 41a, and the tapered tip portion 47aa enters the tapered portion 43c on the exhaust hole 41a side, so that the operation hole 43 can be airtightly closed.

  The operation hole 43 is formed in a circular cross section on the sprue 41 side, and is further provided with grooves 43b at two locations so as to expand the operation hole 43 along a direction orthogonal to the sprue 41. The disk portion 47b is a circular member having an outer diameter substantially the same as the inner diameter of the actuation hole 43, and is substantially the same shape as the two grooves 43b formed in the actuation hole 43. The engaging piece 47ba to be engaged is formed to extend in the radial direction.

The disc portion 47b is disposed so as to be movable back and forth in the length direction of the actuation hole 43 in a state where the engagement piece 47ba is engaged with the groove 43b.
A support portion 46 that slidably holds the sliding portion 47 c is fixed to the operating hole 43 so as to close the operating hole 43. The support portion 46 is formed with a plurality of through holes 46a that penetrate in the sliding direction and allow air movement.

  A coil spring 48 is disposed between the rear surface of the disk portion 47 b and the support portion 46. The coil spring 48 is inserted into the cap portion 47 a from the rear side of the valve body 47. The coil spring 48 urges the valve body 47 toward the sprue 41 side.

  When the valve body 47 is urged by the coil spring 48 and the tip end portion of the cap portion 47a closes the exhaust hole 41a (closed position), the communication hole 45 is closed by the side surface of the disc portion 47b. It has become.

Next, the operation of the mold vacuum valve 40 will be described.
As shown in FIG. 4A, when the electromagnetic valve 59b is closed and the mold vacuum valve 40 is not in communication with the vacuum exhaust means 90, the valve element 47 is attached to the sprue 41 side by the coil spring 48. As a result, the exhaust hole 41a is closed by the tip of the cap portion 47a (closed position).

  On the other hand, when an open signal is sent from the control means 100 to the electromagnetic valve 59b, the electromagnetic valve 59b is opened, and the mold vacuum valve 40 communicates with the vacuum exhaust means 90. Thereby, as shown in FIG. 4B, the air in the operation hole 43 and the exhaust hole 44 is exhausted by the vacuum exhaust means 90.

  At this time, since the operating hole 43 has a larger diameter than the exhaust hole 44, a large suction force acts on the disk portion 47b, and the valve body 47 moves away from the sprue 41 against the biasing force. Slide. The valve body 47 is held at a position (exhaust position) away from the sprue 41 while the air in the cavity 30a is being exhausted.

When the valve body 47 is held at the exhaust position, the exhaust hole 41 a is opened, the communication hole 45 is also opened, and the sprue 41 and the exhaust hole 44 are in communication with each other via the communication hole 45.
As the sprue 41 communicates with the exhaust hole 44, the cavity 30a communicates with the vacuum exhaust means 90 via the mold vacuum valve 40, and the cavity 30a is exhausted to a vacuum state by the vacuum exhaust means 90. The

The control means 100 sends a close signal to the electromagnetic valve 59b after a predetermined time when the cavity 30a is in a vacuum state to make it close. When the pressure in the cavity 30a and the pipe 59 becomes substantially the same, or when the electromagnetic valve 59b is closed, the valve body 47 is forced by the urging force of the coil spring 48 when the air flow from the cavity 30a disappears. Returning to the closing position, the cap 47a closes the exhaust hole 41a.
As described above, the mold vacuum valve 40 of this example can exhaust the cavity 30a through the sprue 41 by opening and closing the electromagnetic valve 59b.

Next, the mold vacuum valve 50 of this example will be described with reference to FIGS.
FIG. 5 is a cross-sectional explanatory view of the mold vacuum valve 50 as viewed from the side of the mold 30.
As shown in FIG. 2, the mold vacuum valve 50 of this example is formed from the end of the product forming surface 32 a of the movable mold 32 to the contact surface between the fixed mold 31 and the movable mold 32. The recessed portion 32e thus formed, and the recessed portion 32f communicating between the recessed portion 32e and the side portion of the movable mold 32 are disposed.

  The mold vacuum valve 50 of this example includes a main body 50a, a valve body 57 that slides within the main body 50a, a coil spring 58 as a biasing means for biasing the valve body 57, and a main body 50a. And an operation hose 53a and an exhaust hose 54a connected to each other, and a connection portion 52 connected to the ends of the operation hose 53a and the exhaust hose 54a. The connecting portion 52 is connected to the pipe 59 and communicates with the operation hose 53a and the exhaust hose 54a.

  The main body 50a is fixed in the recess 32e so that the side surface 50c on the fixed mold 31 side is flush with the contact surface 32b. The operating hose 53a and the exhaust hose 54a are connected to the main body 50a through the recess 32f.

The main body 50 a is formed with an operation hole 53 to which the operation hose 53 a is connected, and an exhaust hole 54 having a smaller diameter than the operation hole 53 in parallel with the operation hole 53.
As shown in FIG. 6, the side surface 50c of the main body 50a is formed with a recess 50b in which the end on the product forming surface 32a side is partially cut away, and the operation hole 53 communicates with the recess 50b. ing.
Further, the recess 50 b and the exhaust hole 54 communicate with each other through a communication hole 55.

  The valve body 57 is disposed in the recess 50b. The closing member 57a slides in the recess 50b in a direction orthogonal to the clamping direction, and the end is attached to the closing member 57a and extends in the sliding direction. And a sliding portion 57c.

  The closing member 57a is slidable with the side surface 57aa on the cavity 30a side being flush with the contact surface 32b and the side surface 50c. The thickness of the side surface 57aa in the sliding direction is set larger than the width of the end 30e of the cavity 30a (the thickness of the end of the molded product). In FIG. 6, a curve Y substantially parallel to the curve X at the end of the product forming surface 32a is a curve at the end of the product forming surface 31a of the fixed mold 31 when the mold is clamped. That is, the end 30e of the cavity 30a is between the curve X and the curve Y.

  As shown in FIG. 5A and FIG. 6, when the closing member 57a is urged and is in contact with the side surface of the recess 32e on the product forming surface 32a side, the recess 57e is recessed from the end 30e of the cavity 30a by the side surface 57aa. The opening 30f communicating with 50b can be closed.

  A support portion 56 that slidably holds the sliding portion 57 c is fixed to the operating hole 53 so as to close the operating hole 53. The support portion 56 is formed with a plurality of through holes 56a that penetrate in the sliding direction and allow air movement.

  A coil spring 58 is disposed between the rear surface of the closing member 57 a and the support portion 56. The coil spring 58 is inserted into the sliding portion 57 c from the rear side of the valve body 57. The coil spring 58 biases the valve body 57 toward the center side of the movable mold 32.

  When the valve body 57 is urged by the coil spring 58 and the side surface 57aa of the closing member 57a closes the opening 30f of the end 30e of the cavity 30a (closed position), it opposes the side surface 57aa of the closing member 57a. The communication hole 55 is blocked by the side surface 57ab.

Next, the operation of the mold vacuum valve 50 will be described.
As shown in FIG. 5A, when the solenoid valve 59b is closed and the mold vacuum valve 50 is not in communication with the vacuum exhaust means 90, the valve element 57 is moved by the coil spring 58 to the movable side mold 32. The opening 30f is closed by the side surface 57aa of the closing member 57a (closed position).

  On the other hand, when an open signal is sent from the control means 100 to the electromagnetic valve 59b, the electromagnetic valve 59b is opened, and the mold vacuum valve 50 communicates with the vacuum exhaust means 90. As a result, as shown in FIG. 5B, the air in the actuation hole 53 and the exhaust hole 54 is exhausted by the vacuum exhaust means 90.

  At this time, since the operating hole 53 has a larger diameter than the exhaust hole 54, a large suction force acts on the closing member 57a, and the valve body 57 resists the urging force of the movable mold 32. Slide to the side. The valve body 57 is held at a position (exhaust position) moved to the side surface side of the movable mold 32 while the air in the cavity 30a is being exhausted.

  When the valve body 57 is held at the exhaust position, the opening 30f opens and the communication hole 55 also opens. In addition, a flow path is formed between the closing member 57a and the side surface of the recess 32e. The cavity 30 a is in communication with the exhaust hole 54 through the flow path and the communication hole 55.

  As a result, the cavity 30a communicates with the vacuum evacuation means 90 via the mold vacuum valve 50, and the cavity 30a is evacuated to a vacuum state by the vacuum evacuation means 90.

The control means 100 sends a close signal to the electromagnetic valve 59b after a predetermined time when the cavity 30a is in a vacuum state to make it close. When the electromagnetic valve 59b is closed or the air flow from the cavity 30a is lost, the valve body 57 returns to the closed position by the urging force of the coil spring 58 and closes the opening 30f by the closing member 57a.
As described above, the mold vacuum valve 50 of this example can exhaust the cavity 30a by opening and closing the electromagnetic valve 59b.

  The mold vacuum valve 50 of the present example is easy to mount because the recesses 32e and 32f are formed in the movable mold 32 and only fixed in the recesses 32e and 32f. In addition, the mold vacuum valve 50 of this example can be easily controlled because the flow path can be switched only by connecting the pipe 59 and reducing the pressure in the pipe 59.

(Hopper evacuation / resin material supply structure)
Next, the material supply unit 20 of this example will be described with reference to FIG. The material supply unit 20 of this example is configured such that the material supply tank 25 that supplies the resin material to the cylinder 11 can be maintained in a vacuum state.
The material supply unit 20 includes a hopper 21, a first supply valve 23 connected to the lower portion of the hopper 21, a cylindrical material supply tank 25 connected to the hopper 21 via the first supply valve 23, and a material supply A second supply valve 26 connected to the lower portion of the tank 25 and a cylindrical material holding portion 27 connected to the material supply tank 25 via the second supply valve 26 are configured as main components.

  The hopper 21 is provided with a sensor 21 a that detects the presence or absence of a predetermined amount of resin material in the hopper 21. The sensor 21a of this example is composed of a phototube. A suction pump 22 is disposed on the hopper 21. A hose 22a is connected to the suction pump 22, and the tip of the hose 22a is inserted into the external tank 3 in which a granular resin material is stored.

  The suction pump 22 operates by receiving a drive signal from the control means 100. When the suction pump 22 is activated, the resin material in the external tank 3 is sucked together with air, and the resin material is transported into the hopper 21 through the hose 22a.

  The first supply valve 23 includes a valve body 23a having a valve for opening and closing an internal passage in an airtight manner, and a valve switch 23b to which a hose for compressed air from the compressed air supply source 4 is connected. The valve switch 23 b supplies compressed air to the valve body 23 a based on the drive signal from the control means 100 to open and close the valve, and detects the open / closed state of the valve and sends an open / close position signal to the control means 100. To do.

  The material supply tank 25 is formed in a substantially cylindrical shape, and a pipe 28 is connected to the center of the side surface. In addition, a vacuum sensor 25 a that measures the atmospheric pressure in the material supply tank 25 and a digital vacuum meter 25 c are attached to the outside of the material supply tank 25. The vacuum sensor 25a displays the internal atmospheric pressure on the display unit. The vacuum meter 25c sends a detection signal obtained by measuring the internal atmospheric pressure to the control means 100, and the control means 100 uses this detection signal for control and display.

  The pipe 28 is connected to a filter 28e on the way, and is branched in two directions on the downstream side of the filter 28e. One of the branches is connected to a vacuum tank 92 via an electromagnetic valve 28a, and the other is connected to an electromagnetic valve 28b and a silencer 28f for opening to the atmosphere. A pipe 59 is joined to the pipe 28 between the electromagnetic valve 28 a and the vacuum tank 92.

A hand valve 28c is connected between the vacuum tank 92 and the electromagnetic valve 28a, and an operator can open and close between the vacuum tank 92 and the electromagnetic valve 28a by the hand valve 28c. The hand valve 28c is normally open.
Further, the pipe 28 is further branched in two directions on the downstream side of the hand valve 28c, and a vacuum tank 92 is connected to one side, and a hand valve 28d is connected to the other side. The hand valve 28d is normally closed. When the hand valve 28d is opened, the vacuum tank 92 is opened to the atmosphere.

  And between the solenoid valve 28a of the piping 28 and the hand valve 28c, the piping 29 connected with the material holding | maintenance part 27 and provided with the material collection | recovery pipe | tube 29e on the way joins.

  The electromagnetic valves 28 a and 28 b are opened and closed in response to a drive signal from the control means 100, and send an open / close position signal to the control means 100. The hand valves 28c and 28d can be manually opened and closed by an operator.

  A vent hole cover 25b having a large number of through holes as shown in FIG. 8A is attached to a connecting portion between the material supply tank 25 and the pipe 28. The vent hole cover 25b is formed by forming a large number of small holes having a diameter smaller than that of a resin material on a circular thin plate made of metal or synthetic resin.

When the inside of the material supply tank 25 is evacuated by the vacuum evacuation means 90, the vent hole cover 25b prevents the resin material from flowing out to the vacuum evacuation means 90 side. Further, the resin material crushed into a powder is recovered by the filter 28e.
As the vent cover 25b, a net-like member made of metal or synthetic resin as shown in FIG. 8B may be used.

A pipe 18 is connected to the side surface of the material supply tank 25. The pipe 18 extends to the nozzle 13 side, and is connected to a heat cover 16 provided in the cylinder 11 via an electromagnetic valve 19. The electromagnetic valve 19 is opened and closed by a drive signal from the control means 100 and sends an open / close position signal to the control means 100.
A vent hole cover 25d similar to the vent hole cover 25b is disposed at the connection portion of the material supply tank 25 with the pipe 18.

  A heat cover 16 is disposed on the outer periphery of the cylinder 11 so as to cover the band heater 15. The heat cover 16 is provided with a suction port 16a and a discharge port 16b, and a pipe 18 is connected to the discharge port 16b. Further, a fan 17 for sending air in the heat cover 16 to the material supply unit 20 side is disposed near the discharge port 16b.

When the band heater 15 is activated, the surrounding air is heated and the temperature of the air in the heat cover 16 rises.
When the electromagnetic valve 19 is opened, the inside of the heat cover 16 and the inside of the material supply tank 25 are communicated via the pipe 18. In a state where the material supply tank 25 is opened to the atmosphere, the hot air in the heat cover 16 is sent into the material supply tank 25 through the pipe 18 by the operation of the fan 17. The resin material is dried and heated by the hot air sent into the material supply tank 25.

  The second supply valve 26 connected to the lower part of the material supply tank 25 has the same configuration as the first supply valve 23. The second supply valve 26 includes a valve body 26a having a valve therein and a valve switch 26b to which a hose for compressed air is connected. The valve switch 26 b supplies compressed air to the valve body 26 a based on the drive signal from the control means 100 to open and close the valve, and detects the open / closed state of the valve and sends an open / close position signal to the control means 100. To do.

  The material holding unit 27 is provided with a sensor 27a. The sensor 27a detects whether or not a predetermined amount of resin material is held in the material holding unit 27 and outputs a detection signal to the control means 100. Sending out. In this example, a photoelectric tube is used for the sensor 27a.

  When the sensor 27a detects the resin material, the sensor 27a sends a signal (filling signal) indicating that a predetermined amount of the resin material is stored to the control means 100. A signal indicating that a fixed amount of resin material is not stored (unfilled detection signal) is sent to the control means 100.

  In this example, when the sensor 27a detects that a predetermined amount of resin material is not stored, it is set so that the resin material corresponding to several injection amounts remains in the material holding unit 27. . And in the injection molding apparatus S of this example, the supply process of the new resin material mentioned later is performed before the resin material which remains in the material holding | maintenance part 27 does not run out.

  In addition, pipes 29 are connected to the lower portion of the material holding unit 27 at two locations. One of the pipes 29 is opened to the atmosphere via a hand valve 29b, the other is connected to a material recovery pipe 29e via a hand valve 29c, and the downstream side of the material recovery pipe 29e is piped via a hand valve 29d. The 28 filters 28e and the solenoid valve 28a are joined together. These hand valves 29b, 29c, 29d are normally kept closed.

  The material recovery pipe 29e has a characteristic configuration of this example, and the resin material remaining in the hopper 21, the material supply tank 25, and the material holding unit 27 when the resin material in the material supply unit 20 is replaced. Is sucked and collected by the vacuum exhaust means 90 and discharged to the outside.

  The material recovery pipe 29e is attached in the middle of the pipe 29, and is constituted by a tubular or bellows-like tubular member made of, for example, resin or metal. Moreover, the attachment part for enabling attachment or detachment in the middle of the piping 29 is provided in both ends. And the filter 29f is provided in the edge part by the side of the piping 28 of the material collection | recovery pipe | tube 29e, as shown in the partially notched cross section of FIG.

The filter 29f is configured such that when sucked by the vacuum exhaust means 90, the resin material flowing in from the material holding portion 27 or the like does not flow out to the downstream side (vacuum exhaust means 90 side). Alternatively, it is possible to use a circular thin plate made of synthetic resin in which a large number of fine holes are formed, or a fine metal or resin net.
The pipe 29 corresponds to the discharge passage of the present invention, and the material recovery pipe 29e provided with the filter 29f corresponds to the recovery means of the present invention.

  In this example, both ends of the material recovery pipe 29e are detachable from the pipe 29, and the material recovery pipe 29e can be removed from the middle of the pipe 29. If comprised in this way, the resin material accumulated inside can be discharged | emitted outside by removing the material recovery pipe | tube 29e from the piping 29. FIG.

  In order to discharge the resin material, it is sufficient that at least the end on the material supply unit 20 side of the end of the material recovery pipe 29e is configured to be detachable from the pipe 29. That is, even if the end on the filter 29f side remains connected to the pipe 29, the end on the material supply unit 20 side can be removed from the pipe 29 and the resin material can be discharged from the opening.

  Further, both ends of the material recovery pipe 29e may be fixed to the pipe 29, and a discharge hole may be formed in the side surface of the material recovery pipe 29e, and a lid member that can be opened and closed is provided in the discharge hole. The lid member can be a resin cap, for example. If comprised in this way, a resin material can be suck | inhaled in the state which closed the discharge | emission hole with the cover member, and if suction | suction is complete | finished, a cover member will be removed, a discharge | release hole will be open | released, and a resin material can be discharged | emitted outside.

(Resin material supply operation)
Next, the operation of supplying the resin material by the material supply unit 20 will be described. The following operation is automatically performed by an operation signal from the control means 100.
Before the injection molding is started by the injection molding apparatus S, the first supply valve 23 and the second supply valve 26 are in an open state, so that the control unit 100 controls the first supply valve 23 and the second supply valve 26. Sends a close signal to enter the closed state.
At this time, the solenoid valves 28a, 28b, and 19 are closed.

  In addition, if the 1st supply valve 23 and the 2nd supply valve 26 are the types which are always a closed state by supply of compressed air (normally closed type), it will be in a closed state by canceling | releasing an open signal. In this specification, when a normally closed valve is in an open state, sending a close signal to close the valve means releasing the open signal. In addition, when the normally open valve is in the closed state, sending an open signal to open the valve means releasing the close signal.

  Since the control means 100 receives a detection signal from the sensor 21a that a predetermined amount of resin material is not in the hopper 21, the control means 100 is driven to the suction pump 22 on condition that the first supply valve 23 is closed. A signal is sent and the suction pump 22 is activated. When receiving a detection signal indicating that a predetermined amount of resin material has been sucked into the hopper 21 from the sensor 21a, the control means 100 stops the suction pump 22. As a result, a predetermined amount of resin material is carried into the hopper 21 from the external tank 3.

  In this example, a sensor 21a is provided in the hopper 21, and the control means 100 detects that a predetermined amount of resin material is filled by a detection signal from the sensor 21a, and stops the suction pump 22. However, the present invention is not limited to this, and instead of providing the sensor 21a, the suction pump 22 is operated for a predetermined time by the drive signal from the control means 100 on the condition that the first supply valve 23 is closed. You may make it carry in a fixed amount of resin material.

  When the suction pump 22 stops, the control means 100 sends an open signal to the first supply valve 23 and the second supply valve 26 to make them open. Thereby, the resin material in the hopper 21 is dropped downward and stored in the material holding portion 27. When the resin material is stored in the material holding unit 27, the sensor 27a detects filling of the resin material, and sends a detection signal indicating that the resin material is in a predetermined amount to the control means 100.

When the control means 100 confirms that the resin material has dropped based on the detection signal from the sensor 27a, the control means 100 sends a close signal to the first supply valve 23 to make it closed.
And when the 1st supply valve 23 will be in a closed state, the control means 100 will operate the suction pump 22 at a predetermined timing, and will store the predetermined amount of resin materials in the hopper 21 again.

  Furthermore, the control means 100 sends an open signal to the electromagnetic valve 28a to make it open, and exhausts the material supply tank 25 and the material holding part 27 to a predetermined degree of vacuum. Further, by exhausting the material holding part 27 to a predetermined degree of vacuum, the inside of the cylinder 11 communicating with the material holding part 27 is also exhausted to a predetermined degree of vacuum.

  In a state where the material holding unit 27 is held at a predetermined degree of vacuum, the resin material is sequentially supplied from the material holding unit 27 into the cylinder 11 heated by the band heater 15, and the resin material is rotated by the rotating screw 12. Is plasticized and kneaded.

Next, a case where the resin material in the material holding portion 27 is insufficient while the resin molding is repeated will be described with reference to FIG. FIG. 9 shows a timing chart.
When the molten resin injection operation is repeated and the resin material accumulated in the material holding unit 27 becomes less than a predetermined amount and the sensor 27a cannot detect the resin material, a detection signal indicating that there is no predetermined amount of resin material is It is sent from the sensor 27a to the control means 100 (a in FIG. 9).

When the control means 100 receives a detection signal indicating that there is no predetermined amount of resin material, the control means 100 sends a close signal to the electromagnetic valve 28a to be in the closed state (b in FIG. 9). Further, the control means 100 sends a close signal to the second supply valve 26 to bring it into a closed state (c in FIG. 9).
In this state, the control means 100 sends an open signal to the electromagnetic valve 28b to set the open state (d in FIG. 9). As a result, the material supply tank 25 is opened to the atmosphere.

  When the electromagnetic valve 28b is in an open state, the control means 100 sends an open signal to the first supply valve 23 to make it open (e in FIG. 9). At this time, since the second supply valve 26 is in a closed state, when the first supply valve 23 is in an open state, a predetermined amount of the resin material falls from the hopper 21 and enters the material supply tank 25. Stored. Further, the sensor 21a sends a signal indicating that there is no predetermined amount of resin material to the control means 100 because the resin material has run out of the hopper 21.

  The control means 100 again supplies the first supply on condition that the resin material in the hopper 21 is detected by a signal from the sensor 21a after a predetermined time has elapsed since the first supply valve 23 is opened. A close signal is sent to the valve 23 to return to the closed state (f in FIG. 9).

  At the timing when the first supply valve 23 is closed, the control means 100 operates the suction pump 22 as described above (m in FIG. 9). When a predetermined amount of resin material is sucked up from the external tank 3, the sensor 27a detects the resin material and sends a detection signal indicating that the predetermined amount of resin material is present to the control means 100 (n in FIG. 9). Thereby, the control means 100 stops the operation | movement of the suction pump 22 (n of FIG. 9).

  When the 1st supply valve 23 will be in a closed state, the control means 100 will send an open signal to the solenoid valve 19, and will be in an open state (g of FIG. 9). Thus, by the operation of the fan 17, hot air in the heat cover 16 is supplied to the material supply tank 25 through the pipe 18, and the resin material in the material supply tank 25 is dried and heated. Hot air is discharged to the outside through the pipe 28 and the electromagnetic valve 28b.

  Thus, whenever the resin material is supplied to the material supply tank 25, it is dried and heated with hot air. As a result, the resin material is easily plasticized and kneaded in the cylinder 11, and the plasticized and kneaded molten resin does not contain moisture and can form a high-quality molded product.

  When a predetermined time elapses after the electromagnetic valve 19 is in the open state, the control means 100 again sends a close signal to the electromagnetic valve 19 to make it close (h in FIG. 9). Further, the control means 100 sends a close signal to the electromagnetic valve 28b to make it close (h in FIG. 9).

  When the electromagnetic valves 19 and 28b are closed, the control means 100 sends an open signal to the electromagnetic valve 28a to open the electromagnetic valve 28a (i in FIG. 9). As a result, the material supply tank 25 is exhausted to a vacuum state by the vacuum tank 92.

  When the control means 100 detects that the material supply tank 25 has been evacuated to a predetermined degree of vacuum based on the detection signal from the vacuum meter 25c, the control means 100 sends an open signal to the second supply valve 26 to make it open (FIG. 9). J). As a result, the material supply tank 25 and the material holding unit 27 communicate with each other, a predetermined amount of the resin material falls from the material supply tank 25 to the material holding unit 27, and the resin material is stored in the material holding unit 27.

When a predetermined amount of resin material is stored, the sensor 27a detects the resin material and sends a detection signal indicating that the predetermined amount of resin material is filled to the control means 100 (k in FIG. 9).
When the sensor 27a detects that the resin material is insufficient (a in FIG. 9), the resin supply process (b to n in FIG. 9) is repeated.

  Thus, in the injection molding apparatus S of this example, the material holding part 27 is always held in a vacuum state during molding. Thereby, the inside of the cylinder 11 is also maintained in a vacuum state, and the resin material can be melted under vacuum.

(Injection molding procedure)
Next, the operation of the injection molding apparatus S of this example will be described based on FIG. FIG. 10 shows a timing chart.
Note that the operation of supplying the resin material in the material supply unit 20 is omitted. In the injection molding apparatus S of this example, the operation of injecting molten resin into the cavity 30a and the operation of supplying the resin material to the material holding unit 27 can be performed independently as described below.

  Thereby, even if the shortage of the resin material in the material holding portion 27 occurs at any stage of the molten resin injection operation, it is possible to continuously form a molded product without interrupting the molten resin injection operation. .

The operator sets the injection unit 10 and the mold clamping unit 80 from the operation unit 103 in advance.
The control unit 100 sends an operation signal to the mold clamping unit 80 to clamp the movable mold 32 and the fixed mold 31 with a predetermined mold clamping pressure.

When the mold is clamped, a detection signal is sent from the position detection switch 88 to the control means 100 (A in FIG. 10).
When the control means 100 receives the detection signal, it sends an open signal to the electromagnetic valve 59b to make it open (B in FIG. 10). Thereby, the mold vacuum valves 40 and 50 are opened, and the cavity 30a is exhausted to a predetermined degree of vacuum.

  When the control means 100 detects from the detection signal from the vacuum meter 59c that the cavity 30a has been evacuated to a predetermined degree of vacuum, after a predetermined time, the control means 100 sends a close signal to the electromagnetic valve 59b to enter the closed state (FIG. 10). C).

An operation signal is sent from the control means 100 to the drive unit 14, and the screw 12 is rotated. By this rotation, the resin material supplied from the material supply unit 20 into the cylinder 11 is sent to the front of the cylinder 11, and the molten resin is supplied. Accumulated in front of the cylinder 11.
Since the resin material is plasticized and kneaded under vacuum as described above, gas and moisture generated by melting the resin material are removed.

  In this state, the control unit 100 sends an operation signal to the drive unit 14 of the injection unit 10, moves the screw 12 forward, and injects a predetermined amount of molten resin from the nozzle 13 into the cavity 30a (FIG. 10). D).

After injection of the molten resin, after a predetermined cooling time has elapsed, the control means 100 sends an operation signal to the injection means 10, and the injection means 10 moves the screw 12 backward (E in FIG. 10).
When screwed back, the control means 100 sends an operation signal to the mold clamping means 80 to retract the movable mold 32 and open the mold (F in FIG. 10). At this time, a detection signal indicating that the mold has been opened is sent from the position detection switch 88 to the control means 100.
Then, the ejector pin 36A is operated to take out the molded product from the mold (G in FIG. 10).

The injection molding apparatus S repeats the processes such as the mold clamping process, the evacuation process, the injection process, the cooling process, the mold opening process, and the like to continuously form molded products.
In addition, when the cylinder 11 is shifted in the front-rear direction every time the molding is performed and the nozzle 30 is touched by the nozzle, the cylinder 11 is touched after the mold is clamped to exhaust the cavity 30a and screw back. Can be made to retreat.

  In the injection molding apparatus S of this example, the cavity 30a can be held in a vacuum state at the time of injection. Accordingly, there is almost no air resistance at the time of molding, and the molten resin can be spread quickly and uniformly to every corner of the cavity 30a with a small injection pressure.

Therefore, uneven color, cracks, sink marks, burns, weld lines, shorts, etc. do not occur in the molded product. For example, even if the molded product is a long deep object such as a reinforcing rib or a fine mesh (lattice), insufficient filling does not occur.
Moreover, in the injection molding apparatus S of this example, since the molten resin is filled quickly and uniformly as described above, a molded product with extremely small internal stress can be molded.

(Removal operation of resin material)
Next, the operation of sucking the resin material remaining in the material holding portion 27 and the like after completion of molding into the material recovery pipe 29e and discharging it to the outside will be described.
When the injection molding apparatus S finishes the molding process and takes out the resin material from the material holding unit 27 or the like, first, the operation unit 103 of the control means 100 is operated to close the electromagnetic valve 28a and open the electromagnetic valve 28b. Put it in a state. Thereby, the pipe 28 and the material supply tank 25 are opened to the atmosphere, and the passage of the pipe 28 to the vacuum exhaust means 90 is blocked.

  And the operation part 103 of the control means 100 is operated, and the 1st supply valve 23 and the 2nd supply valve 26 are made into an open state. As a result, the resin material stored in the hopper 21 and the material supply tank 25 moves to the material holding unit 27.

  Next, the hand valve 29 c is opened, and the pipe 29 and the material holding unit 27 are communicated. Further, the hand valve 29d is opened, and the pipe 29 and the pipe 28 are communicated. Thereby, the material holding | maintenance part 27 is connected with the piping 28 in the downstream of the solenoid valve 28a via the piping 29 in which the material collection | recovery pipe | tube 29e was provided in the middle.

  When the operation unit 103 of the control unit 100 is operated to activate the vacuum exhaust unit 90, the resin material in the material holding unit 27 is sucked to the vacuum exhaust unit 90 side through the pipe 29. By this suction force, the resin material remaining in the material holding part 27 flows out to the pipe 29 side and flows into the material recovery pipe 29e. At this time, since the filter 29f is provided on the downstream side (vacuum exhaust means 90 side) of the material recovery pipe 29e provided in the middle of the pipe 29, the sucked resin material is located downstream of the filter 29f. Will not be leaked. On the other hand, the sucked air is exhausted to the outside by the vacuum exhaust means 90.

  When the resin material flows into the material recovery pipe 29e, the operation of the vacuum exhaust means 90 is stopped and the hand valves 29c and 29d are returned to the closed state. Then, the material recovery pipe 29e is removed from the pipe 29, and the resin material accumulated inside is discharged to an external recovery container or the like.

  As described above, the resin material stored in the hopper 21, the material supply tank 25, the material holding unit 27, and the like can be sucked by the vacuum exhaust means 90 and moved to the material recovery pipe 29e to be recovered. In this example, the vacuum evacuation means 90 corresponds to the suction means of the present invention.

  As described above, in the injection molding apparatus S of the present example, safety management of shifting the hopper 21, the material holding portion 27, and the like with respect to the cylinder 11 is necessary, and opening and closing of the valve and vacuum evacuation are performed without performing laborious work. By means 90, the resin material can be reliably recovered. In addition, in such a method, there is no inconvenience that the resin material spills onto the floor surface and the like, so that the recovery operation can be performed easily and quickly.

(Resin Material Discharge Structure and Discharge Operation: Other Examples)
Next, based on FIG. 11, the material supply part 120 of another Example is demonstrated. In the material supply unit 20, the resin material is sucked and collected by the vacuum evacuation means 90, but in this example, a separate suction pump is provided to suck the resin material. Hereinafter, the configuration and operation of the material supply unit 120 of this example will be described only for the parts different from the material supply unit 20, and the description of the same parts will be omitted.

  In this example, the suction pump 129a is connected to the downstream side of the pipe 129 on the hand valve 129c side among the pipes 129 connected to the lower part of the material holding unit 27. A hand valve 129d is connected to the downstream side of the suction pump 129a, and the downstream side of the hand valve 129d is connected to a pipe 28 between the electromagnetic valve 28b and the filter 28e. A collection container (not shown) is provided inside the suction pump.

Next, the discharging operation of the resin material in this example will be described.
First, similarly to the above embodiment, the operation unit 103 of the control means 100 is operated to close the electromagnetic valve 28a and open the electromagnetic valve 28b, and open the pipe 28 and the material supply tank 25 to the atmosphere. At the same time, the passage of the pipe 28 to the vacuum exhaust means 90 is blocked. Then, the first supply valve 23 and the second supply valve 26 are opened, and the resin material stored in the hopper 21 and the material supply tank 25 is moved to the material holding unit 27.

  Next, the hand valve 129d is opened, and the suction pump 129a and the pipe 28 are communicated. Further, the hand valve 129c is opened, and the suction pump 129a and the material holding unit 27 are communicated.

  When the operation unit 103 of the control unit 100 is operated to operate the suction pump 129a, the resin material in the material holding unit 27 is sucked into the suction pump 129a through the pipe 129 and collected in an internal collection container. Is done. The sucked air passes through the pipe 129 and is released to the outside through the electromagnetic valve 28b.

When the resin material is completely recovered, the operation of the suction pump 129a is stopped, and the hand valves 129b, 129c, and 129d are returned to the closed state. When the resin material is accumulated up to the full capacity of the collection container or when it is necessary to use the collected resin material outside, the collection container is removed from the suction pump or the discharge port provided in the collection container is opened. The internal resin material is discharged to the outside.
In this way, the resin material stored in the hopper 21, the material supply tank 25, and the material holding unit 27 can be recovered. In this example, the suction pump 129a corresponds to the suction means of the present invention, and the recovery container corresponds to the recovery means of the present invention.

  In this example, the suction pump 129a is connected to the pipe 28 via the hand valve 129d, but the downstream side of the hand valve 129d may be opened to the atmosphere.

(Modification 1)
In each of the above-described embodiments, if the operation unit 103 of the control unit 100 is operated so that the first supply valve 23 is closed and the hand valve 29b or the hand valve 129b is opened, the material is retained. The resin material remaining in the portion 27 can be completely sucked and collected.

(Modification 2)
In each of the above embodiments, the hand valve (29b, 29c, 29d, 129b, 129c, 129d) is used. However, the present invention is not limited to this, and a solenoid valve that is normally closed (normally closed) that can be opened and closed by the control means 100 is used. It may be used. In this case, the resin material recovery operation can be performed simply by operating the operation unit 103 of the control means 100.

It is explanatory drawing of the injection molding apparatus which concerns on one Embodiment of this invention. It is explanatory drawing of the metal mold | die which concerns on one Embodiment of this invention. It is explanatory drawing of the control means which concerns on one Embodiment of this invention. It is explanatory drawing of the metal mold | die vacuum valve which concerns on one Embodiment of this invention. It is explanatory drawing of the metal mold | die vacuum valve which concerns on one Embodiment of this invention. It is explanatory drawing of the metal mold | die vacuum valve which concerns on one Embodiment of this invention. It is explanatory drawing of the material supply part which concerns on one Embodiment of this invention. It is explanatory drawing of the vent hole cover of the material supply part which concerns on one Embodiment of this invention. It is a timing chart of the material supply part which concerns on one Embodiment of this invention. It is a timing chart of the metal mold | die vacuum valve which concerns on one Embodiment of this invention. It is explanatory drawing of the injection molding apparatus which concerns on other embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Frame, 3 External tank, 4 Compressed air supply source 10 ... Injection means 11 ... Cylinder, 12 ... Screw, 13 ... Nozzle 14 ... Drive part 15 ... Band heater, 16 ... Heat cover, 17 ... Fan 18 ... Piping, 19 ... Solenoid valve 20 ... Material supply section 21 ... Hopper, 21a ... Sensor 22 ... Suction pump, 22a ... Hose 23 ... First supply valve, 23a ... Valve body, 23b ... Valve switch 25 ... Material supply tank, 25a Vacuum sensor, 25c Vacuum meters 25b and 25d Vent cover 26 Second supply valve, 26a Valve body, 26b Valve switch 27 Material holding section, 27a Sensor 28 Piping 28a, 28b Solenoid valve 28c 28d Hand valve
28e ... Filter, 28f ... Silencer 29 ... Piping, 29b, 29c, 29d ... Hand valve 29e ... Material recovery pipe, 29f ... Filter 30 ... Mold, 30a ... Cavity 31 ... Fixed side mold 32 ... Movable side Mold 33A ... Fixed side mounting plate 35 ... Ejector plate 36A ... Ejector pin 37A ... Movable side mounting plate 40 ... Mold vacuum valve 41 ... Sprue 50 ... Mold vacuum valve 59 ... Piping, 59a ... Vacuum sensor 59b Solenoid valve 59c Vacuum meter 80 Clamping means 81 Fixed die plate 82 Moving die plate 90 Vacuum exhaust means 90a Vacuum sensor 90b Vacuum meter 91 Vacuum Pump 92 92 Vacuum tank 100 Control means 101 Control unit 102 Display unit 103 Operation unit 120 Material supply unit 129 Piping 29a ‥ suction pump 129b, 129c, 129d ‥ hand valve S ‥‥‥ injection molding apparatus X, Y ‥ curve

Claims (6)

A mold having a cavity formed by a fixed mold and a movable mold, mold clamping means capable of clamping the mold, and an injection unit for melting a resin material and injecting molten resin into the cavity; An injection unit having a material supply unit for supplying a resin material to the injection unit,
The material supply unit includes a discharge unit for discharging the resin material,
The discharge section is connected to the material supply section, a suction means for sucking the resin material together with air through the discharge path, and the suction resin material that is connected to the discharge path and flows into the interior. Recovery means,
The injection means is characterized in that the recovery means is configured to be able to discharge the inflowing resin material to the outside. A vacuum exhaust means for evacuating the cavity;
2. The injection molding apparatus according to claim 1, wherein the material supply unit is connected to the vacuum evacuation unit and is capable of supplying the resin material to the injection unit in a state of being held under vacuum.   The injection molding apparatus according to claim 2, wherein the vacuum evacuation unit functions as the suction unit.   The recovery means is made of a tubular member having a filter member at one end, and is attached in the middle of the discharge passage so that the end on the filter member side is located on the suction means side. The injection molding apparatus according to any one of claims 1 to 3.   The injection molding apparatus according to claim 4, wherein the tubular member is configured such that an end portion on the material supply unit side is detachable from the discharge passage. A mold having a cavity formed by a fixed mold and a movable mold, mold clamping means capable of clamping the mold, and an injection unit for melting a resin material and injecting molten resin into the cavity; In an injection molding apparatus comprising: an injection unit having a material supply unit for supplying a resin material to the injection unit; and a vacuum exhaust unit for evacuating the cavity, the resin material introduced into the material supply unit A resin material recovery method for discharging
Supplying the injection means in a state where the material supply unit is evacuated to hold the resin material under vacuum;
In a state where the material supply unit communicates with the outside air, the resin material is sucked together with air through the discharge passage communicated with the material supply unit, and flows into the collection means attached in the middle of the discharge passage. Step to make,
A step of discharging the resin material from the recovery means to the outside; and a resin material recovery method in an injection molding apparatus.

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