JPH02223417A - Injection molding machine - Google Patents

Abstract

PURPOSE:To enable favorable injection molding without following flashes, by a method wherein plungers are provided respectively within plurality of measuring cylinders so that plungers are capable of performing reciprocation in an axial direction and at the time of backward movement, the plunger is stopped at a position where capacity of the measuring cylinder becomes that corresponding to that of a cavity. CONSTITUTION:When resin plasticized with a plasticizing device 20 is sent into a plurality of measuring cylinders 35, plungers 38 within measuring cylinders 35 each are moved until capacity of the measuring cylinders 35 each becomes that corresponding to that of a plurality of cavity 53a, 53b in a mold 50 provided by corresponding to the measuring cylinders each. With this construction, necessary quantity of resin is measured respectively every cavities 53a, 53b each. The resin is injected into the cavities 53a, 53b each completely at a time, by pressurizing the resin measured within the measuring cylinder 35 by moving the plungers 38 each forward by a moving device 39.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an injection molding machine, and particularly to an injection molding machine having a plurality of cavities in a mold.

[Conventional technology]

Conventionally, as this type of injection molding machine, the one shown in FIG. Heater 3...
is wound, and a screw 4 is provided inside the heating cylinder 2 so as to be movable back and forth. The screw 4 is rotated by a hydraulic motor or the like and moved forward by a hydraulic cylinder or the like, and a backflow prevention ring 5 is provided at the tip of the screw 4 so as to be movable back and forth. A nozzle 6 in which a through hole 6a is formed is provided at the tip of the heating cylinder 2. A mold 7 consisting of a fixed mold 8 and a movable mold 9 is placed at a position facing this nozzle 6.
is installed, and the tip of the nozzle 6 is brought into contact with one end surface of the fixed mold 8, so that the through hole 6a and the sprue l of the fixed mold 8 are connected.
It is designed to communicate with O. The sprue IO is branched in the middle and opens into a plurality of cavities 11, 12 of different sizes in the mold 7.

In the injection molding machine configured as described above, when the screw 4 is rotated, the resin in the hopper 1 is plasticized and passes between the backflow prevention ring 5 and the screw 4 to form the tip 2a in the heating cylinder 2. is stored in In this case, as the plasticized resin is stored, the screw 4 is retracted,
Weighing is performed based on this amount of retreat. When the tip 2a is smoothly filled according to the cavity 11, 12, the rotation of the screw 4 is stopped.

Next, when the scree 4 is advanced, the rear end surface of the backflow prevention ring 5 comes into close contact with the screw 4, and the plasticized resin is injected through the through hole 6a of the nozzle 6, passes through the sprue 10, and enters the mold 7. The cavities 11 and 12 are filled.

[Problem to be solved by the invention]

By the way, in the injection molding machine described in item 1, the resin plasticized and measured by the heating cylinder 2 and the screw 4 is
Even if the injection is made through the through hole 6a of the nozzle 6, the cavity 1
1 and cavity 12 are not filled with resin at the same time. That is, when filling of the resin into the cavity 11 with a small capacity is completed, there is still a portion of the cavity 12 with a large capacity that has not been filled. For this reason, the pressurizing conditions, cooling time, etc. are different between the resin in the cavity 11 and the resin in the cavity 12, resulting in problems such as the formation of flakes in the resin in the cavity I1.

As a way to solve this problem, cavity 11.1
It is conceivable to provide the same number of heating cylinders 2 and screws 4 as the number of cavities 11 and 12 (that is, two), perform a total of I corresponding to the cavities 11 and 12, and inject at the same time. However, this method has the problem of requiring a large-scale and expensive apparatus.

The present invention was made in view of the above circumstances, and its purpose is to be able to measure resin into a plurality of cavities with different capacities, and to simultaneously inject resin into each cavity. Our goal is to provide injection molding machines that can be completed.

[Means to solve the problem]

In order to achieve the above object, the injection molding machine of the first invention has the following features:
An injection molding machine in which resin is plasticized, measured, and injected into a plurality of cavities in a mold, and the plasticizing device is provided between a plasticizing device that plasticizes the resin and the mold. A plurality of measuring cylinders are provided which are capable of communicating with each other, and each of the above-mentioned cavities is capable of communicating with each other, and a plunger is provided within each of these measuring cylinders so as to be able to reciprocate in the axial direction. The planter is provided so as to be stopped at a position where the capacity corresponds to the capacity of the cavity or the capacity of the cavity, and a moving means is provided for moving the planter forward at the same time.

Further, a second invention provides the injection molding machine of the first invention, wherein the plurality of measuring cylinders are provided on a rotary disc that is fitted to the support shaft portion of the fixed plate so as to be relatively rotatable in the circumferential direction, The support shaft is provided with an introduction passage that communicates with the plasticizing device, and the support shaft and the rotary disk are provided with passages that communicate with the introduction passage and a measuring cylinder in a radial manner. .

[Effect]

In the injection molding machine of the first invention, when the resin plasticized by the plasticizing device is fed into the plurality of charge cylinders,
The plunger in each metering cylinder is moved until the capacity of each metering cylinder corresponds to the capacity of a plurality of cavities in the mold provided correspondingly to each metering cylinder. In each case, the required amount of resin is measured. And by means of transportation,
By moving each of the plungers forward and pressurizing the resin metered into the metering cylinder, injection of resin into each cavity is completed at the same time.

The injection molding machine of the second invention operates in the same manner as the injection molding machine of the first invention, but the feeding of resin into the plurality of measuring cylinders is achieved by communicating the plasticizing device with the introduction passage of the support shaft, and
Further, the rotary disk is rotated in the circumferential direction relative to the support shaft, and the passage provided in the support shaft is communicated with the passage provided in the rotary disk.

In the above configuration, the passages provided in the support shaft and the rotary disk for communicating the metering cylinder with the introduction passage are provided radially around the introduction passage, so the passage between the introduction passage and the metering cylinder is The lengths can be made almost the same, and they can be easily processed.

〔Example〕

Embodiments of the injection molding machine of the present invention will be described below with reference to the drawings.

(First Embodiment) FIGS. 1 and 2 are diagrams showing a first embodiment of the present invention.

In the drawings, reference numeral 20 denotes a plasticizing device, which includes a heating cylinder 21 and a screw 22 provided inside the heating cylinder 21 so as to be movable back and forth. The screw 22 is rotated by a hydraulic motor or the like, and is moved forward by a hydraulic cylinder or the like. Reference numeral 30 denotes a cylindrical fixed plate, and an annular recess 31 is provided on the end surface 30a of the fixed plate 30.
is formed. The fixed platen 30 also includes an end surface 30a.
A passage 32 communicating with the circumferential surface 31a of the recess 31 is formed therein. This passage 32 includes an introduction passage 32a formed linearly in a direction perpendicular to the end surface 30a, and an introduction passage 32a formed linearly in a direction perpendicular to the end surface 30a.
An annular passage 32b branched from 2a and formed in a circular shape when viewed from the end surface 30a side, and a plurality of branch passages 32c with one end opening in the annular passage 32b and the other end opening into the recess 31.
・It is composed of. The introduction passage 32a is connected to the plasticizing device 20. Further, the fixed platen 30 is formed with a plurality of through holes 33 that communicate from the bottom surface 31b of the recess 31 to the end surface 30b. Each through hole 33 has an end face 3
They are arranged at equal intervals on the same circumference when viewed from the 0a side.

A cylindrical rotary plate 34 is fitted into the recess 31 of the fixed plate 30 so as to be rotatable about the support shaft portion 30c of the fixed plate 30. This rotary plate 34 includes a support shaft portion 3 of the fixed plate 30.
The same number of cylinders 35 (measuring cylinders) as the through holes 33 are formed parallel to and through 0c, and these cylinders 35 correspond to the arrangement circle of the through holes 33 when viewed from the end surface 30a of the fixed platen 30. They are arranged at equal intervals on a circumference with the same diameter as the circumference. In addition, each cylinder 3 is provided on the rotary disk 34.
A plurality of passages 36 are formed from the passages 5 to the outer circumferential surface 34a. As shown in FIG. 2, a movable rod 37a of a hydraulic cylinder 37 whose base end is pivotally connected to a fixed portion is pivotally connected to the rotary disk 34, and the rotary disk 34 is rotated by this hydraulic cylinder 37. It is designed to be moved. As shown in FIG. 2, when the movable rod 37a extends, the rotary disk 34 rotates in the X direction, and each passage 36 and each branch passage 32c of the passage 32 of the fixed plate 30 communicate with each other. When the movable rod 37a moves back, the rotary disk 34 rotates in the Y direction and the cylinders 35 do not communicate with the through holes 33 of the fixed plate 3.
5 and each through hole 33 of the fixed plate 30 (at this time, each passage 36 and each branch passage 32 of the passage 32 of the fixed plate 30 communicate with each other).
c). A plunger 38 is fitted into each cylinder 34 so as to be movable back and forth in its axial direction. 39 is a hydraulic cylinder (moving means), and a movable rod 40 of this hydraulic cylinder 39
A disk-shaped suppressing member 41 is fixed to the tip of the holder.

A plurality of adjustment screws 42... are screwed into the pressing member 4■, and each adjustment screw 42 can be adjusted to either the fixed platen 34 or the state shown in FIG.
Each passage 36 is provided at a position corresponding to each plunger 38, with each passage 36 communicating with each branch passage 32c of the fixed plate 3°.

50 is a mold consisting of a fixed mold 51 and a movable mold 52. The mold 50 is provided with the same number of cavities 53a, 53b, . . . (eight in this embodiment) as the through holes 33 of the fixed platen 3o (therefore, the same number as the cylinders 35). These cavities 53a, 53b have different capacities. The fixed mold 51 has each cavity 53a,
A plurality of sprues 54a, 5 each leading to 53b...
4b... is formed. These sprues 54a,
54b is connected to each through hole 33 of the fixed platen 30, respectively.

By adjusting the protrusion length from the end surface 41a of the pressing member 41, each of the adjusting screws 42 stops the movement of each plunger 38 when it moves toward the suppressing member 41, and each cavity 53a, 53b... The amount of resin filled into each cylinder 35 is set according to the capacity of the cavity, and if the capacity of the cavity is small, the resin will protrude more from the end face 41a.

Next, the operation of the injection molding machine configured as described above will be explained.

With each passage 36 of the rotary plate 34 and each branch passage 32c of the passage 32 of the fixed plate 30 communicating with each other, the resin plasticized by the plasticizing apparatus 20 in the same manner as in a conventional injection molding machine is transferred to the plasticizing apparatus. 20 to the passage 32 of the fixed plate 30 and the rotary plate 3
When fed into each cylinder 35 through each passage 36 of 4,
As the resin flows into each cylinder 35, each plunger 38 moves backward toward each adjustment screw 42, comes into contact with each adjustment screw 42, and stops. When all the plungers 38 come into contact with their corresponding adjustment screws 42, the supply of resin is stopped.

Next, the rotary disk 34 is rotated in the Y direction in FIG. 2 by the hydraulic pressure/link 37, so that each cylinder 35 and each through hole 33 are communicated with each other. At this time, the positions of each adjustment screw 42 and each plunger 38 are shifted.

Next, the movable rod 40 of the hydraulic cylinder 39 is extended by a predetermined length. In this way, the end surface 4 of the pressing member 41]
Each plunger 38 is pushed forward by a, and the resin in each cylinder 35 is injected into the through hole 33..., sprue 54a, 54b..., respectively. In this case, the distance to each cavity 53a153b is equivalent to (the length obtained by subtracting the protruding length of each adjusting screw 42 from the end surface 41a of the pressing member 41 from the extended length of the movable rod 40)X (the area of the cylinder 350). amount of resin is injected. That is, each adjusting screw 42 from the end surface 41a of the pressing member 41
By adjusting the protrusion length of each cavity 53
It is possible to measure the injection amount according to each of a, 53b, and so on.

Next, after retracting the movable rod 40 of the hydraulic cylinder 39, the rotating disk 34 is rotated in the X direction in FIG. communicate. After that, repeat the above operation.

In such an injection molding machine, the resin plasticized by the plasticizing device 20 can be measured in each cylinder 35 according to the capacity of each cavity 53a, 53b, and so on. The measured resin is transferred to hydraulic cylinder 3.
9, injection can be completed simultaneously into each cavity 53a153b. Therefore, it is possible to perform good molding without the occurrence of flakes.

Further, since the injection amount of each plunger 38 is adjusted by each adjustment screw 42, there is an advantage that the injection amount can be easily changed when the capacity of the cavity changes.

Further, in the above embodiment, each cylinder 35 has the same inner diameter, and the moving distance of each plunger 38 is adjusted by each adjustment screw 42 to measure the amount of injection into each cavity 53a153b. and the diameter (area) of each plunger 38, each cavity 53a, 53
You may use one that is changed depending on the capacity of b... In this case, since the moving distances of each plunger 38 can be made the same, each plunger 38 can be brought into direct contact with the end surface 41a of the pressing member 41 without providing each adjustment screw 42.

(Second Embodiment) FIG. 3 is a diagram showing a second embodiment. In this figure, the same components as in FIGS. 1 and 2 are denoted by the same reference numerals, and detailed explanation thereof will be omitted.

In this embodiment, vacuum forming and injection molding are performed.

In FIG. 3, reference numeral 60 is a mold consisting of a female mold 6I and a male mold 62. The female mold 61 is provided with a plurality of through holes 63 for vacuum extraction, and each through hole 63 is connected to a vacuum pump or the like (not shown). Also, female type 61
have cavities 64a, 64b, 64c with different capacities.
...is provided.

65 is a plastic sheet.

Next, the operation of the injection molding machine configured as described above will be explained.

The resin plasticized by the plasticizing device 20 is metered into each cylinder 35 in the same manner as in the device of the previous embodiment.

In the next step, the heated plastic sheet 65 is placed into the female mold 61.
and the male mold 62, and after lowering the female mold 61 or raising the male mold 62 and sandwiching them between them, the female mold 61 and the plastic sheet 65 are removed from each through hole 63 using a vacuum pump or the like. The air between them is discharged, and the plastic sheet 65 is brought into close contact with the female mold 61.

Next, the hydraulic cylinder 39 pumps the resin in each cylinder 35 into each cavity 64a, 64b.

64c... Inject inward. In this way, since the plastic sheet 65 is also heated, the resin injected into each cavity 6.4a, 64b, 64c, . . . is completely welded to the plastic sheet 65.

In addition to the effects of the first embodiment, such an injection molding machine has the following effects.

In other words, vacuum forming is suitable for forming large, thin-walled products that are difficult to make with injection molding, but in principle, it is not possible to form products with a wall thickness greater than that of the sheet, so some parts of the molded product may have ribs, In the past, if a thick part such as a boss was desired to be provided, this could not be done at the time of molding, and the only solution was to mold it separately and then glue it in a separate process. For this reason, after molding, they were joined using an adhesive or welded, resulting in poor production efficiency. In the injection molding machine of this embodiment, ribs, bosses, etc. can be provided at the same time as vacuum forming, so production efficiency can be improved, and furthermore,
It is possible to form well even thick parts such as ribs and ribs of different sizes.

Furthermore, since the bosses and ribs are formed while the plastic sheet 65 is heated, it is possible to obtain bosses and ribs that are stronger than those that are bonded together.

(Third example) FIG. 4 is a diagram showing a third embodiment.

In FIG. 4, reference numeral 70 indicates a cylinder member,
A plurality of cylinders (measuring cylinders) 71 having the same size and shape are formed in the cylinder member 70, and a plunger 72 is fitted into each cylinder 71 so as to be able to reciprocate in the axial direction thereof. An adjustment bolt 73 is screwed into the end surface 72a of each plunger 72, respectively. 74 is a hydraulic cylinder (moving means), and a flat pressing member 76 is fixed to the tip of a movable rod 75 of this hydraulic cylinder 74. A plurality of through holes 76a are bored in this pressing member 76, and each of the adjustment bolts 73 is inserted through each through hole 76a and screwed onto the plunger 72, respectively. 77 is a flat stopper arranged opposite to the head 73a of the adjustment bolt 73.

Each cylinder 71 has a plurality of cavities 78a, 78b, 78c with different capacities formed in a mold.

78d through passages 71a, 71b, 71c, and 71d, respectively. In addition, the plasticizing device 20
are connected to the passage 71 via check valves 79, respectively.
a, 7lb, 71c, and 71d. Passage 71 a, 7 l b, 71
There is an opening/closing means (not shown) on the cavity side of c and 71 d.
is provided.

Each adjustment bolt 73 is connected to an end surface 72a of the plunger 72.
By adjusting the protruding length from each cavity 78a, 78b, when each plunger 72 moves toward the stopper 77, this movement is stopped.

The amount of resin filled into each cylinder 7I is set according to the capacity of the cavities 78c and 78d, and when the capacity of the cavity is small, the resin protrudes more from the end face 72a.

Next, the operation of the injection molding machine configured as described above will be explained.

When the resin plasticized by the plasticizing device 20 is fed into each cylinder 71 by closing the passages 71a, 71b, 71c, and 71d using the opening/closing means, as the resin flows into each cylinder 71, the resin flows toward the plunger 72 or the stopper 77. The adjusting bolts 73 then come into contact with the stoppers 77 and stop. When all the plungers 72 stop, the supply of resin is stopped. In this case, the end surface 72a of the plunger 72
By adjusting the protrusion length of each adjustment bolt 73 from each cavity 78a, 78b, 78c.

It is possible to measure the amount of resin according to each of 78d.

Next, the opening/closing means of the passages 71a, 71b, 71c, and 71d are opened to extend the movable rod 75 of the hydraulic cylinder 74. In this way, each plunger 72 is pushed forward by the end surface 76a of the pressing member 76, and the resin in each cylinder tough 1 is released into each cavity 78a, 7.
8b, 78c.

It is injected within 78d.

After injection is completed, the movable rod 75 of the hydraulic cylinder 74
Move back and repeat the above operation.

In the injection molding machine as described above, the resin plasticized by the plasticizing device 20 is introduced into each cylinder 71 into each cavity 78a, 78b, 78c.

78d, and the measured resin can be simultaneously injected into each cavity 78a, 78b, 78c, and 78d by the hydraulic cylinder tuff 4. Therefore, good molding can be carried out without the occurrence of flakes.

In addition, check valves 79 are provided between the plasticizing device 20 and each cylinder tough 1, so that the resin can be removed from the cavities 78.
When injecting into the insides of a, 78b, 78c, and 78d, the resin does not flow back into the plasticizing device 20 side.

Furthermore, since the structure is simple, it has the advantage that it can be manufactured at low cost.

(Fourth Example) FIG. 5 is a diagram showing a fourth example. In FIG. 5, the same components as those in FIG. 4 are given the same reference numerals, and detailed explanation thereof will be omitted.

In FIG. 5, reference numeral 80 denotes a cylinder member,
A plurality of cylinders (measuring cylinders) 81.8I having the same -TI method shape are formed in this cylinder member 80,
A plunger 82 is fitted into each cylinder 81 so as to be movable back and forth in its axial direction. The plunger 82 is formed with a medium diameter portion 82a having a slightly smaller diameter and a small diameter portion 82b having a smaller diameter than the medium diameter portion 82a.

A backflow prevention ring 83 is provided in the small diameter portion 82b so as to be movable back and forth in the axial direction. An adjustment port 73 is screwed into the end surface 82c of each plunger 82, respectively.

Each cylinder 81 is individually connected to a plurality of cavities 84a, 84b having different capacities formed in the mold through passages 81a, 81b having opening/closing means (not shown). Further, each cylinder 81 is connected to a plasticizing device 20, respectively.

Each adjustment bolt 73 is connected to the end face 82c of the plunger 82.
When each plunger 82 moves toward the stopper 77, this movement can be stopped by adjusting the length of the projection from the cylinder 81, and the amount of resin filled into each cylinder 81 can be adjusted according to the capacity of each cavity 84a, 84b. is to be set,
If the cavity capacity is small, the end face 82c
projected from.

Next, the operation of the injection molding machine configured as described above will be explained.

When the resin plasticized by the plasticizing device 20 is fed into each cylinder 81 by closing the passages 81a and 81b with the opening/closing means, as the resin flows into each cylinder 81,
The plunger 82 moves backward toward the stopper 77, and each adjustment screw 73 comes into contact with the stopper 77 and stops. When all the plungers 82 stop, the resin supply is stopped. In this case, each adjustment screw 7 from the end face 82c of the plunger 82
By adjusting the protrusion length of 3, each cavity B
The amount of resin corresponding to each of 4a and 84b can be measured.

Next, the opening/closing means of the passages 81a and 81b are opened to extend the movable rod 75 of the hydraulic cylinder 74.

In this way, each plunger 82 is pushed and moved forward by the end surface 76a of the pressing member 76, and the resin in each cylinder 81 is released into each cavity 84a 8.
4b is injected within. At this time, backflow prevention ring 8
In FIG. 3, the upper end surface is in close contact with the plunger 82 to prevent the resin from flowing back toward the plasticizing device 20.

After injection is completed, move the movable port of the hydraulic cylinder tough 4 and the door 5.
Move back and repeat the above operation.

In the injection molding machine as described above, the resin plasticized by the plasticizing device 20 can be measured in each cylinder 8I according to the capacity of each cavity 84a, 84b, and The resin can be injected into each cavity 84a, 84b simultaneously by the hydraulic cylinder 74. Therefore, good molding can be performed without the occurrence of flakes.

In addition, since a backflow prevention ring 83 is provided on the plunger 82, when injecting resin into the cavities 84a and 84b,
The resin will not flow back to the plasticizing device 20 side.

Furthermore, since the structure is simple, it has the advantage that it can be manufactured at low cost.

(Fifth example) FIGS. 6 and 7 are diagrams showing a fifth embodiment of the present invention.

The fixed platen 30 of this injection molding machine is constructed by fixing a bottom plate 30f to one end of a cylindrical member 30e integrally with a plurality of bolts 90.
Fixed by A support shaft portion 30g is provided at the center of the bottom plate 30f. The support shaft portion 30g has a circular cross section and protrudes at the center of the cylindrical member 30e.

The rotary disk 34 is fitted onto the support shaft portion 30g and the cylindrical member 30
e so as to be rotatable in the circumferential direction, and the bottom plate 30f and the support plate 8
It is held between the shoulder 85c of the insertion hole 85b of No. 5 and is fitted so as not to move in the axial direction.

An introduction passage 30h is formed in the center of the support shaft 30g, and the open end thereof is a notch 3oj against which a nozzle (not shown) of a plasticizing device comes into contact. Further, in the support shaft portion 30g, a plurality of passages 30m (in each case, eight in the figure) are opened on the outer peripheral surface of the support shaft portion 30g and are radially formed at equal intervals in the circumferential direction. aisle 30
The position of the passageway 30m is shifted in the length direction of the introduction passageway 30h, and the phase is shifted by 1/2 pitch.

Further, the cylindrical member 30e has passages 30k, 30m...
・The same number of connection ports 30n, 30p, etc. are the passage 30k.

It is installed at a position corresponding to 30m. Connection 03
0 n, 30 p... are connected to the mold cavity via piping or the like. The rotary disk 34 is provided with a plurality of cylinders (measuring cylinders) 35a, 35b, . . . (8 cylinders each in the figure). Cylinder 35a...
The cylinders 35b, .
They are arranged in an annular shape at equal intervals around the center of rotation of the rotary disk 34, and 1/2 pitch out of phase with the cylinder 35a. At the outer opening end of each of the cylinders 35a, 35b, .

In the rotary disk 34, cylinders 35a, 35b, . . . are connected to a passage 30k at one rotational position of the rotary disk 34.

passages 34b and 34c each communicating with 30m;
At other rotational positions, passages 34d communicate the cylinders 35a, 35b with the connection ports 30n, 30p, respectively.
, 34e... are formed radially and linearly with respect to each other. A plurality of support rods 86 (four pieces of wood in the figure) are erected on the support plate 85, and a fixed plate 8 is attached to the tip of the support rods 86.
A hydraulic cylinder 39 is fixed to 7, and a pressing member 41 fixed to a movable rod 40 of this hydraulic cylinder 39 is supported and guided by a pair of the support rods 86 and moves toward and away from the rotary disk 34. It is about to be moved.

The hydraulic cylinder 37 has a base end rotatably supported by a support pin 37b on a bracket 88 fixed to the support plate 85 and a support rod 86, and its movable rod 37a is connected to the support plate 85 of the rotary disk 34. It is rotatably connected to a metal fitting 89 fixed to the outer periphery of the protruding end.

6 and 7, reference numeral 91 is a heater band, 92 is a sheathed heater, 93 is a cylinder 35a,
Plug 9 closing the end on the bottom plate 30f side of 35b...
Reference numeral 4 denotes a plug that closes one end of the introduction passage 30h.

The other structure of this embodiment is the same as that of the injection molding machine shown in FIGS. 1 and 2, so the same reference numerals are given and detailed explanation will be omitted. It goes without saying that the volume of the cylinder 35a35b can be changed by adjusting the adjustment screw 42 forward or backward.

The operation of the injection molding machine of this embodiment is basically the same as the injection molding machine of the first embodiment shown in FIGS. 1 and 2.

That is, the nozzle of the injection molding machine is connected to the nozzle touch part 30j.
30h and the resin into the introduction passage 30h and the passage 30.
Each cylinder 35a, 35b is filled through the passages 34b, 34c (see FIG. 6).

Next, the rotary disk 34 is rotated by a predetermined angle (225 degrees in the figure) by the operation of the hydraulic cylinder 37, so that each cylinder 35
a, 35b passages 34 d, 34 e to connection port 30n,
30p, actuate the hydraulic cylinder 39 to push the plunger 38 with the suppressing member 41, and each cylinder 35a,
The plurality of cavities of the mold are filled with the resin in 35b.

The number of cavities in the mold is small and all cylinders 35 a
, 35b, push the plunger 38 into the unused cylinders 35a, 35b, screw the male screw 38a of the plunger 3 days into the acid screw 35c of the rotary disk 35, and then tighten the plunger 38. The tips lead to passages 34b, 34c, 34d.

34e is closed, and the resin is introduced from the introduction passage 30h to the passage 30k.

Avoid entering the cylinders 35a and 35b after 30 m.

In this injection molding machine, since the distances from the introduction passage 30h to each cylinder 35a, 35b are approximately equal, the resin filling conditions can be made equal to improve metering accuracy. Moreover, passages 34b, 34. d.

34C and 34e linearly pass through the rotary disk 34, and 30m also passes through the passage 30 from the outer circumferential surface of the support shaft portion 30g to the introduction passage 30h, making it easy to process them.

〔Effect of the invention〕

As explained above, in the injection molding machine of the first invention, when the resin plasticized by the plasticizing device is fed into the plurality of measuring cylinders, the capacity of each measuring cylinder corresponds to that of each measuring cylinder. The plunger in each metering cylinder moves until the capacity corresponds to the capacity of a plurality of cavities in the mold provided in the mold, thereby making it possible to meter the required amount of resin for each cavity.

Then, by moving each of the plungers forward by the moving means and pressurizing the resin metered into the measuring cylinder, injection of the resin into each cavity can be completed at the same time. Therefore, it is possible to perform good molding without overfilling a particular cavity with resin and causing burrs or the like.

In addition, in the injection molding machine of the second invention, in addition to achieving the same effect as the first invention, the introduction passage is provided at the center of rotation of the rotary disk, and the passages extending radially from there provide the injection molding machine for each cylinder. Since the distance from the introduction passage to each cylinder is approximately equal, resin filling conditions can be made equal to improve metering accuracy and to equalize product quality. In addition, the passageway is easy to process.

[Brief explanation of the drawing]

1 and 2 are diagrams showing a first embodiment of the present invention, in which FIG. 1 is a sectional view showing a schematic configuration, and FIG. 2 is a view taken along the line ■-■ in FIG. 1. . FIG. 3 is a diagram showing a second embodiment of the present invention, and is a sectional view showing a schematic configuration. Fourth
The figure shows a third embodiment of the present invention, and is a sectional view showing a schematic configuration. FIG. 5 is a diagram showing a fourth embodiment of the present invention, and is a sectional view showing a schematic configuration. 6 and 7 are views showing a fifth embodiment of the present invention, in which FIG. 6 is a sectional view and FIG. 7 is a partially cut away bottom view. 8th
The figure is a diagram showing a conventional embodiment, and is a sectional view showing a schematic configuration. 20...Plasticizing device 30...Fixed plate 30g・
・Support shaft part 30h...Introduction passage 30k, 30m
, 34 b, 34c...Passage 34 Turntable 35.71.81...Cylinder (measuring cylinder) 3B
, 72.82...Plunger 39.74...Hydraulic cylinder (moving means) 50.60...
・Mold 53a 53b...Cavities 64a, 64b, 64cm...Cavity 78a,
78 b, 78 c, 78 d-...
Cavities 84a, 84b...Cavities

Claims (2)

[Claims] (1) An injection molding machine in which resin is plasticized, measured, and injected into a plurality of cavities in a mold, and the plasticizer is placed between a plasticizing device that plasticizes the resin and the mold. A plurality of measuring cylinders are provided which are capable of communicating with the converting device and are capable of communicating with each of the cavities, and each of the plungers is reciprocated in the axial direction within these measuring cylinders, and when the plunger is moved backward, The measuring cylinder is provided so as to stop at a position where the capacity corresponds to the capacity of the cavity, and the plunger is
An injection molding machine characterized by being provided with a moving means for simultaneous forward movement. (2) In the injection molding machine described in paragraph 1, the plurality of measuring cylinders are provided on a rotary plate that is fitted to the support shaft portion of the fixed plate so as to be relatively rotatable in the circumferential direction, and An injection molding machine characterized in that the support shaft portion is provided with an introduction passage communicating with a plasticizing device, and the support shaft portion and the rotary disk are provided with passages radially communicating with the introduction passage and a metering cylinder.