JPS60240428A - Injection molding machine - Google Patents

Abstract

PURPOSE:To enable the miniaturization of an injection molding machine by forming into a tiebar a piston head located inside a cylinder chamber provided on a movable die plate and at the same time, forming in the tiebar the first and second flow channels feeding hydraulic oil to the right section or the left section of the chamber. CONSTITUTION:A tiebar 39 is installed between a stationary die plate 20 and an adapter plate 38 on a movable side and a die opening/closing cylinder 18 is arranged around a tiebar 39. Then a piston head located inside a chamber 19 of the die opening/closing cylinder 18 is formed into a tiebar 39 and the tiebar 39 is capable of acting as a die opening/closing piston. In addition, the first flow channel 41 and the second flow channel 42 are formed in a tiebar shape 39 at the right section or the left section of the chamber 19 for supplying hydraulic oil. Under this constitution, the machine is not complicated without exposing an oil feeder pipe. Furthermore, curvature radius need not be considered during pipe laying, so that space for piping can be reduced.

Description

[Detailed description of the invention] This invention relates to an injection molding machine.

As is well known, an injection molding machine consists of an injection device that melts the supplied plastic material and injects it into the cavity of a die, a mold clamping device that applies a predetermined mold clamping force to the die, and an injection device and a mold clamping device. The injection molding machine is equipped with a hydraulic drive section that supplies pressurized oil to a hydraulic cylinder that drives the machine, and a frame that supports the injection device, mold clamping device, and hydraulic drive section and serves as the base of the injection molding machine. In order to supply pressurized oil to actuators such as hydraulic cylinders, a large number of oil feed pipes such as high pressure rubber hoses are provided. However, the oil pipe is exposed to the outside and requires a considerable area for installation, and in addition, a certain radius of curvature must be given to the oil pipe for piping. Also,
Accessories such as switching valves are also arranged externally, and installation requires space.

Therefore, the configuration becomes complicated and a large amount of dead space is created, which hinders miniaturization of the injection molding machine.

(Objective of the present invention is to provide an injection molding machine that can be disposed without any problems, thereby reducing dead space, thereby making it possible to downsize the machine.)

A piston head located in a chamber of a cylinder provided on a movable die plate is formed into a tie bar.

First and second channels are formed in the tie bar to supply pressurized oil to the right or left portion of the chamber.
The movable Goui plate is reciprocated by supplying pressurized oil to the chamber through the flow path. In such a configuration, the first and second channels that act as oil pipes are not exposed and there is no need to consider the radius of curvature of the oil pipe, so the installation area of the oil pipe is unnecessary. , the dead space is significantly reduced, thus making it possible to downsize and provide a compact injection molding machine.

Embodiments of the present invention will be described in detail below with reference to the drawings.

As shown in FIG. 1, the injection molding machine 10 includes an injection device 12 that melts the supplied plastic material and injects it into the cavity 1 of the die, and a mold clamping device 14 that applies a predetermined mold clamping force to the die. Equipped with: In a known injection molding machine, a mold clamping device is provided on a movable die plate, and a mold clamping piston connected to a movable die is reciprocated within a chamber of a mold clamping cylinder to open and close the die. is pressed against a fixed die to generate mold clamping force.

In contrast, in the illustrated embodiment, the movable die plate) 1
The cylinder 18 provided at B is used for opening and closing the die, and the fixed die 21 is indirectly connected to the piston 2B that reciprocates within the chamber 24 of the cylinder 22 provided on the fixed die plate 20. Generates tightening force. Note that the fixed die 21 is attached to the fixed guide plate 20 so as to be movable in the direction of the movable die 17.

In this way, the mold clamping device 14 includes two sets of cylinders: the mold opening/closing cylinder 18 in the movable die plate 16 and the mold clamping cylinder 22 in the fixed die plate 20. Furthermore,
A protruding cylinder 28 is provided on the movable gouging plate 16 and constitutes a part of the movable gouging plate 16. A protruding piston 32 is disposed within a chamber 30 of the protruding cylinder 28 so as to be able to reciprocate. Further, a protruding plate 34 is attached to the movable die 17 so as to be movable in the axial direction, and the tip of a protruding piston 32 is fixed to the back surface of the protruding plate 34. A plurality of ejector pins 36 for ejecting the molded product in the cavity 11 are attached to the ejector plate 34.
is attached to the front of the A tie bar 38 is installed between the fixed guide plate 20 and the movable adapter plate 38, and the mold opening/closing cylinder 18 is arranged around the tie bar 38. A piston head located within the chamber X8 of the mold opening/closing cylinder 18 is formed in the tie bar 38, so that the tie bar 38 functions as a mold opening/closing piston. Further, a first flow path 41 and a second flow path 42 are formed in the tie bar 39 to supply pressurized oil to the right or left portion of the chamber 19. In this way, the tie bar 38 acts as a mold opening/closing piston, and the first passage 41 and the second passage 42 for supplying pressurized oil to the chamber 19 of the mold opening/closing cylinder 18 are connected to the tie bar 38.
8 is not complicated. Further, there is no need to consider the radius of curvature when piping, and dead space can be eliminated, and the space for piping can be significantly reduced compared to the conventional method. Therefore, the mold clamping device 14 can be downsized, and a compact injection molding machine 10 can be provided.

A spline 28 is formed on the outer periphery of the small diameter left end of the protruding cylinder 28, and a corresponding spline 45 is formed on the inner periphery of a lock block 44 rotatably attached to the movable adapter plate 38. Here, when the protruding cylinder 28 moves forward together with the movable guide plate +8 and reaches the mold clamping position, the right end of the lock block 44 connects with the left end of the protruding cylinder 28, leaving a slight gap to allow rotation. It is configured to be able to face each other. These splines 2S, 45 constitute locking means for the movable gouly plate 16. That is, when the perturbation die play) 1B moves forward or backward, these splines 29.45
are aligned to allow movement of the movable die plate (1B) as shown in the right half of FIG. After the movable die plate (1B) moves forward to the mold clamping position, the lock block 44
By rotating, as shown in the left half of Figure 2,
The movable gouging plate 16 is locked by shifting the spline 45 of the lock block 44.

The injection device 12 includes an injection plunger 48 that injects molten plastic into the cavity 11 through a nozzle 48. The injection plunger 48 is not directly connected to the injection ram 5o, and the head 52 of the injection plunger 48 is movably arranged in a high pressure chamber 54 formed in the injection ram 50. This high pressure chamber 54 has a flow path 56
A branch flow path 5 is connected to the chamber 24 of the mold clamping cylinder 22 via the
8 to the nozzle cylinders 58 and chambers BO, chambers 24, 54, 60, flow passages 5B, 58, respectively.
is filled with oil. A nozzle piston 61 connected to the rear end of the nozzle 4B is movably disposed within the chamber 60. Further, flow paths 62 and 63 communicating with the chamber 64 are formed in the injection cylinder θ8.

A launch discharge plate 68, which is an intermediate plate, is supported by the tie bar 38 and is movably attached to the fixed die plate 20, and furthermore, the gouey fixed plate 7° is moved to the fixed goui plate 20 via the launch discharge plate 68. installed as possible. And fixed die play)2
A runner discharge cylinder 72 is formed at the slider 74.
is disposed so as to be able to reciprocate within the chamber 73 of the launch discharge cylinder 72 around the tie bar 39. Further, around this slider 74, another slider 76 is inserted into the chamber 73.
It is arranged so that it can freely reciprocate inside. And slider 7
The tip of the slider 76 is fixed to the goo fixing plate "?0", and the tip of the slider 76 is fixed to the launch discharge plate 68.In addition, contrary to the embodiment, the slider 74 may be arranged around the slider 78. .

Regarding the flow path system, a flow path 78 is formed in the right part of the chamber 73 of the runner discharge cylinder 72, and a flow path 8o is formed in the fixed gou plate 20 to supply pressurized oil to the left part of the chamber 73. There is. In addition, the chamber 73
A flow path 82 is formed in the fixed Goi plate 20 to communicate the left and right parts of the guide plate 20 . The aforementioned second flow path 42 formed in the tie bar 39 for supplying pressurized oil to the left portion of the chamber 19 of the mold opening/closing cylinder 18 has a branch flow path 84 at the tip, and this branch flow path 84 has a branch flow path 84 at its tip. It is formed so as to be able to communicate with a third flow path 8θ that communicates with the left portion of the chamber 30 of the protruding cylinder 28.

Here, when the movable guide plate 16 begins to move from the mold opening position toward the mold clamping position, the communication between the branch flow path 84 and the third flow path 86 is cut off, and the third flow path 88 is connected to the right portion of the chamber 19. will be communicated to. In other words, the third flow path 8B is the first flow path 41
will be communicated to. In addition, the fourth flow path 88 is a movable die plate)
1B, one end of which communicates with the right portion of the protruding cylinder 28, and the other end of which communicates with the right portion of the chamber 18 of the mold opening/closing cylinder 1B.

In addition, reference number 80.81 is an annular groove for the flow path 5B,
Reference numeral 82 indicates a sprue bush, and reference numeral 84 indicates a binge runner.

The operation of the injection molding machine IO having the above configuration will be explained below. In FIG. 1 showing the mold opening position, when pressurized oil is supplied to the right part of the chamber 19 of the mold opening/closing cylinder 18 through the first flow path 41, the movable die plate or die moves forward, that is, to the right. Moving. Further, since the fourth flow path 88 communicates with the right portion of the chamber 19, the pressurized oil also flows into the right portion of the chamber 30 of the protruding cylinder 28 via the fourth flow path 88. Therefore, the protruding piston 32 moves to the left and retreats the ejector pin 36 on the protruding plate 34 to peek out from inside the cavity 11. Here, when the movable gouly plate 1B starts moving forward, the third flow path 88 also moves into the chamber. Pressurized oil also flows into the left part of the chamber 30 of the protruding cylinder 28 . However, the protruding piston 32 is designed so that the force trying to move the protruding piston 32 to the right is smaller than the force trying to move the protruding piston 32 to the left, so there is no problem.
As B moves forward, the splines 28 formed on the protruding cylinder 28 are aligned with the splines 45 on the locking block 44, as shown in the right half of FIG. After the movable die plate 1B moves to the mold clamping position (see FIG. 3) where the movable die 17 is pressed against the fixed die 21, the lock block 44 is moved by a gear train so as to shift the spline 45 to a position where it is not aligned with the spline 29. , a drive belt, a linkage, or other known means. spline 2
8.45 are not aligned, no movement of the protruding cylinder 28 to the left is allowed and therefore the movable die plate 16
is locked in the clamping position.

After locking the movable die plate hlB in the mold clamping position shown in FIG. 3, molten plastic is injected into the cavity 11. That is, in order to inject the molten plastic into the cavity 11, pressurized oil is sent via the flow path 62 to the right part of the chamber 64 of the injection cylinder 66. injection ram 5
0 moves forward together with the injection plunger 48, and the molten plastic in front of the injection plunger 48 flows through the nozzle 46. It is injected into the cavity 11 via the sprue bush 82. Here, the pressure of the molten plastic increases to the injection plunger 4.
As the injection ram 50 advances, the oil pressure in the high pressure chamber 54 increases due to the reaction force on the injection ram 50 . This oil pressure passes through the flow path 58 and enters the chamber 2 of the mold clamping cylinder 22.
4 and presses the mold clamping piston 26 to the left. The oil pressure in the high pressure chamber 54 is higher than the injection pressure due to the viscosity of the molten plastic, and furthermore, because the cross-sectional area of the chamber 24 is significantly larger than that of the high pressure chamber 54, a very large force is applied to the clamping piston 26. It acts on Here, the mold clamping piston 28 is designed so that its cross-sectional area is larger than that of the molded product, and the force generated within the cavity 11 acting in the direction of opening the die (
mold clamping force) is generated on the mold clamping piston 26. This mold clamping force is
It is transmitted to the fixed die 21 via the launch discharge plate θ8, and pushes the fixed die 21 in the direction of the movable die 17. and,
Since the movable gouging plate 16 is locked by the lock block 44, a large mold clamping force is generated between the movable gouging plate 16 and the fixed die plate 20. In this way, the pressure acting on the injection plunger 48 is reduced to the fixed die 21.
In the configuration in which the mold clamping force is generated by transmitting the mold clamping force to the mold clamping force, a large mold clamping force is generated without increasing the size of the mold clamping cylinder as in the past, and the mold clamping device 14 can be made smaller. A small injection molding 41110 can be provided. Further, the flow path 56 is connected to the injection plunger 48. Since the injection cylinder 68 is disposed inside the tie bar, the oil pipe is not exposed and dead space is prevented, simplifying Ia formation and allowing injection molding@
10 can be further downsized. In addition, since the annular groove 80 is formed in the middle of the flow path 58, the injection plunger 4
8 moves, the hydraulic pressure within the high pressure chamber 54 is reliably transmitted to the mold clamping cylinder 22. Further, the pressurized oil in the high pressure chamber 54 is transmitted to the chamber bO of the nozzle cylinder 59 via the branch flow path 58 of the flow path 58, and moves the nozzle piston 61 forward. Therefore, the nozzle 46 connected to the nozzle piston 61 is pressed against the sprue bush 82 with sufficient pressure, and can inject the molten plastic into the cavity 11 without leaking. Furthermore, since the pressing force is transmitted to the fixed die 21 via the sprue bush 82, an even greater mold clamping force acts between the fixed die 21 and the movable die 17. Note that, as the pressure acting on the injection plunger 48, the molten plastic in front of the injection plunger 48 may be introduced into the chamber 24.80, and the pressure of the molten plastic may be applied to the piston 28.61.

At this time, it goes without saying that the mold clamping cylinder 22 and the nozzle cylinder 58 are heated with heaters to prevent the molten plastic from hardening.

After molding, molten plastic is supplied to the front of the injection plunger 48 through a feeder (not shown), so that the injection plunger 4B retreats together with the injection ram 50.

After that, in Figure 3 showing the mold clamping position for mold opening,
First, the lock block 44 is rotated so that its splines 45 are aligned with the splines 28 of the protruding cylinder 28 to unlock the movable gouging plate 16 and allowing the movable gouging plate 16 to retreat. Then, the second flow path 42
Then, pressurized oil is sent to the left part of the chamber 18 of the mold opening/closing cylinder 18, and the movable Goui plate 1G is moved backward, that is, to the left. Movable die play) 1B moves back enough,
When the mold is in the open position shown in FIG.
Through the third flow path 86, the chamber 3o of the protruding cylinder 28
flows into the left part of At this time, the first flow path 41 is in a drain state and no hydraulic pressure is acting on the right part of the chamber 30. Therefore, the protruding piston 32 moves forward and the ejector pin 38 moves as shown in FIG. cavity l
1 and protrude the molded product from the cavity 11,
Drop into a suitable molding container (not shown). As mentioned above, the third passage 86 allows the second passage 42 to communicate with the left portion of the chamber 30 of the protruding cylinder 28 when the movable gouie plate 16 is in the mold open position, and also allows the movable gouie plate 16 to communicate with the left portion of the chamber 30 of the protruding cylinder 28. When in the closed position, the first passage 41 is communicated with the left portion of the chamber 30 of the protruding cylinder 28 . In other words, the third flow path 88 has a function as a switching valve, and the arrangement of the switching valve is omitted, so the dead space is reduced and the configuration is simplified, making the mold clamping device 14 and the injection molding machine 10 more compact. can.

Furthermore, when the movable gouly plate 1B retreats to open the mold, pressurized oil is sent to the right portion of the chamber 73 of the launch discharge cylinder 72 via the wave passage 78 in FIG.

Then, the slider 74 moves to the left, and the slider 74
The gooey fixing plate 70 connected to the tip of the lunch discharge plate 68 is moved forward to separate the gooey fixing plate 70 from the lunch discharge plate 68. Thereafter, as shown in FIG. 4, the slider 74 comes into contact with the slider 78 and moves further to the left together with the slider 7B. Since the slider 7θ is pressed by the slider 74 and moves together with the slider 74, the launch discharge plate 68 fixed to the tip of the slider 7θ is
Move away from the fixed Goi plate 20 and move the Goi fixed play) 7
Move in the direction of 0. That is, first, the gooey fixing plate 7° is separated from the lunch discharge plate 68, and then,
The lunch discharge plate 6th is separated from the fixed Gui plate 2o. Therefore, the bin gate runner 84 located between the fixed gouer 21, the lunch discharge plate 68, and the sprue bush 92 is reliably discharged.

Further, in this way, the lunch discharge plate 68 is provided on the fixed guide plate 20, and the lunch discharge cylinder 7
Channels 78, 80.
In the configuration in which 82 is formed on the fixed guide plate 20 and the oil pipe is exposed, the injection fitting old 2 is miniaturized.
Downsizing of the injection molding machine 10 is promoted.

Note that after the bin gate runner 84 is discharged, the flow path 78 is placed in a drain state.

After the ejection of the molded product and the discharge of the bin gate runner θ4 are completed, the mold is clamped. For mold clamping, in FIG.
It is sent to the left half of the chamber 73 of No. 2. Then, the sliders 74 and 78 first move backward, that is, to the right, as one unit. When the lunch discharge plate 68 moves until it comes into contact with the fixed guide plate 20.

The slider 76 cannot move any further, but in this state, pressurized oil is sent from the left part of the chamber 73 to the middle part via the flow path 82, causing the slider 74 to move further to the right. The slider 74 then moves to the right until the gooey fixing plate 70 comes into contact with the lunch discharge plate 88.

At the same time or after sending pressurized oil to the flow path 80, the first
Pressurized oil is supplied to the right part of the chamber 1B of the mold opening/closing cylinder 18 through the flow path 41, and the movable guide plate 1B
is moved forward, that is, to the right, and the mold clamping cycle described above is started. Thereafter, it goes without saying that the injection cycle and mold opening cycle described above are repeated.

As described above, according to the present invention, the piston head located in the chamber of the cylinder provided in the movable die plate is formed in the tie bar, and the first, In such a configuration, the movable guide plate is reciprocated by forming a second channel in the chamber and supplying pressurized oil to the chamber via the first and second channels. The first and second flow paths that act as pipes are not exposed, and there is no need to consider the radius of curvature of the oil pipe.Therefore, installation of the oil pipe does not require any area, and dead space is significantly reduced. This also simplifies the configuration. Therefore, the mold clamping device can be downsized, and a compact injection molding machine can be provided.

In the embodiment, a cylinder in the movable gouging plate acts as a mold opening/closing cylinder, and another cylinder is provided in the movable gouging plate which acts as a mold closing cylinder. Here, the cylinder in the movable gouly plate may be configured to act as a clamping cylinder, but as in the embodiment,
The mold opening/closing cylinder is made into a movable guide plate! X! It is preferable that the clamping scissor cylinder is provided on the movable gouging plate, and the pressure acting on the injection plunger is guided to the mold clamping cylinder to press the fixed gouging in the direction of the movable gouging. With such a configuration, the high pressure acting on the injection plunger can be used as mold clamping force, so there is no need to increase the size of the cylinder in the movable gouging plate, and the mold clamping device can be downsized. Therefore, the injection molding machine can be further downsized.

In addition, a protruding cylinder is provided on the movable gouly plate, and a second flow path is provided in the left part of the chamber of the protruding cylinder when the movable gouly plate is in the mold open position, and when the movable gouly plate (I8) is in the mold clamping position, It is preferable that the movable gouy plate is formed with a third flow path that communicates with the first flow path, and a fourth flow path that communicates the first flow path with the right portion of the chamber of the protruding cylinder. With this configuration, the oil feed pipe is not exposed and the third flow path has the function of a switching valve, so the switching pulp can be omitted. Therefore, the dead space for piping is reduced, the configuration is simplified, and the mold clamping device is made smaller, which further promotes the miniaturization of injection molding machines. Moreover, the following advantages can be obtained.

(1) The installation area can be reduced, and the injection molding machine can be placed directly on the assembly line. Furthermore, the molding process can be carried out nearby, and the cost of transporting the molded product can be reduced.

(2) Since the injection molding machine can also serve as a mother mold for gooey, a mother mold is not required.

(3) Since the gouging can be changed just by handling, gouging maintenance and setup can be done easily.

(4) When using the same goo, the number of injection molding machines can be increased according to the production quantity, so there is no need to manufacture multiple goues at the trial production stage, and the transition from trial production to mass production is easy.

(5) It becomes possible to produce a small number of pieces, eliminate variations in quality, and enable high-quality molding. In addition, even if the molding machine or injection molding machine breaks down, it is possible to produce a small number of pieces, so the production of molded products will not stop completely.

The above-mentioned embodiments are for illustrating this invention, and do not limit the number of ships of this invention, and any modifications, modifications, etc. that are made within the technical scope of this invention are within the scope of this invention. Needless to say, it is included.

[Brief explanation of drawings]

1 and 3 are longitudinal sectional views of the injection molding machine according to the present invention in the mold opening position and the mold clamping position, and FIG.
FIG. 4 is a partial left side view of the injection molding machine with the movable gouging plate locked and unlocked, after ejection of the molded product and ejection of the bingate runner have been completed. FIG. 2 is a partial vertical sectional view of an injection molding machine. lO: injection molding machine, 11: cavity, 12: injection device, 14: mold clamping device, 18: movable die plate), 1
7: Movable gouly, 18: Mold opening/closing cylinder, 19: Mold opening/closing cylinder chamber, 20: Fixed gouey plate, 21: Fixed gouey, 22: Mold clamping cylinder, 24: Mold clamping cylinder chamber, 28: Mold clamping piston, 28: Projection cylinder, 2
9: Spline of protruding cylinder, 30: Chamber of protruding cylinder, 32: Protruding piston, 313: Tie bar, 4
1 = first flow path, 42 = second flow path, 44: lock block, 45: spline of lock block, 48: injection plunger, 50: injection ram, 54: high pressure chamber, 68:
Injection cylinder, 68 Two launch discharge plates, 70: Gui fixing plate, 72: Launch discharge cylinder, 73: Launch discharge cylinder chamber, 74.78 Varnish slider, 7
8.80.82: Channel, 86: Third channel, 88: Fourth channel, 94: Pin gate runner. Applicant Tsuois Co., Ltd. Agent Patent Attorney Takao Warashina

Claims (2)

[Claims] (1) The piston head located in the chamber of the cylinder provided on the movable die plate is formed to be tight <-, and the first and second flow paths are provided to supply pressurized oil to the right or left part of the chamber. forming the tie in the first,
An injection molding machine in which a movable goo plate is reciprocated by supplying pressurized oil to a chamber through a second flow path. (2) A protruding cylinder is provided on the movable gouly plate, and a second flow path is provided on the left side of the protruding cylinder when the movable gouly plate is in the mold opening position, and a second flow path is provided in the left part of the protruding cylinder when the movable gouly plate is in the mold closing position. At this time, a third flow path that connects the first flow path and a channel/channel of the protruding cylinder that connects the first flow path to the first flow path are connected to each other.
2. The injection molding machine according to claim 1, wherein the movable guide plate has a fourth flow path communicating with the right portion of the movable guide plate.