JPS6356046B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a mold opening device that can open a mold using only a mold clamping cylinder, for example in a predetermined rubber compression injection molding machine.

Conventional technology Conventionally, as this type of molding machine, the molding machines shown in Figs.
There is one shown in the figure. This molding machine includes a fixed die plate 1, a movable die plate 4 to which a lower die 5 is attached via a hot plate 6, a clamping cylinder 3 for operating the movable die plate 4, and a fixed die plate 1.
an upper die holding plate 10 that is movable between the fixed die plate 1 and the movable die plate 4;
0 and a plunger 24 attached to the fixed die plate 1 via a hot plate 25, the plunger 24 enters into the injection pot 28 when the mold is closed as shown in FIG. However, as the rubber material on the upper mold holding plate 10 or the injection pot 28 is heated, it is simultaneously compressed, flows, and flows into the cavity within the mold. After the molding is completed, when the piston rod 3a of the mold clamping cylinder 3 descends, the mold is opened as shown in FIG. Therefore, the upper die holding plate 10 is forcibly lowered by a piston rod 30a of a hydraulic cylinder 30 dedicated to opening the die, which is attached to the fixed die plate 1. However, if there is a hydraulic cylinder 30 dedicated to opening the mold, a hydraulic valve and an electric control circuit are required to operate the hydraulic cylinder 30, which only complicates the structure of the machine and the maintenance and inspection of the machine. However, it also had the disadvantage of being expensive to produce.

Purpose The purpose of the present invention is to remove the upper mold holding plate from the injection pot without using the hydraulic cylinder dedicated to opening the mold, and instead use only the mold clamping cylinder for operating the movable die plate. It is an object of the present invention to provide a mold opening device that can eliminate the above-mentioned drawbacks by making the mold opening process possible.

Structure of the Invention The first invention has been made to achieve this object in a molding machine in which the mold has both upper and lower molds, and when the mold is opened, the upper mold holding plate is forcibly lowered as the movable die plate lowers. In addition to providing an engaging means for engaging with the upper die holding plate, an upper die positioning stopper means for regulating the lowering limit of the upper die holding plate is also provided.

The second invention is made to achieve this object in a molding machine in which the mold is composed of an upper mold, a middle mold, and a lower mold, and in addition to the configuration of the first invention, the lowering limit of the middle mold holding plate is regulated. A medium-sized positioning stopper means is provided.

Embodiment An embodiment of the present invention will be described below with reference to FIGS. 3 to 12. Tie bars 1a are erected and fixed on the four corners of the lower fixed frame 2, and the upper ends of these tie bars 1a are A fixed die plate 1 is fixed to the frame 2, and a mold clamping cylinder 3 is attached to the lower surface of the frame 2. This mold clamping cylinder 3
A movable die plate 4 is mounted on the piston rod 3a.
A lower mold 5 is mounted on the movable die plate 4 via a hot plate 6. A connecting rod 7 is erected and fixed on the four corners of this movable die plate 4, a pipe 7a is inserted into the upper half of this connecting rod 7, and engaging portions 8, 9 is formed. This connecting rod 7 is connected to the insertion holes 11 formed in the four corners of the upper die holding plate 10.
It is movably inserted into the The lowering limit of the upper die holding plate 10 is regulated by two upper die positioning stoppers 12 which are erected and fixed on the frame 2 through the insertion holes 4a of the movable die plate 4. An upper mold 13 is attached to the upper mold holding plate 10, and a rubber material 14 is placed at the center of the upper surface of the upper mold 13.

The pipe 7a of the connecting rod 7 is movably inserted into insertion holes 16 formed at the four corners of the connecting plate 15 above the fixed die plate 1. The lowering limit of the connecting plate 15 is determined by a medium-sized positioning stopper 17 protruding from the center of the upper surface of the fixed die plate 1.
It is becoming regulated by A connecting rod 18 is fixed to the die plate 1 on one side of the connecting plate 15.
The connecting rod 18 is suspended and fixed through the insertion holes 19 and 20 of the upper die holding plate 10, and a central holding plate 21 is fixed to the lower end of the connecting rod 18. The upper die positioning stopper 12 is provided on one side of the middle die holding plate 21.
An insertion hole 22 into which is movably inserted is formed. A middle die 23 is attached to this middle die holding plate 21 so as to be located between the lower die 5 on the movable die plate 4 and the upper die 13 on the upper die holding plate 10.

A plunger 24 is attached to the center of the lower surface of the fixed die plate 1 via a hot plate 25. Further, a pair of guide bars 27 are movably inserted into the insertion holes 26 formed in the fixed die plate 1, and the lower limit of the guide bars 27 is between the engaging portion 27a at the upper end and the fixed die plate 1. It is designed to be regulated by engagement with the upper surface. An injection pot 28 is attached to the lower end of the guide bar 27 below the fixed die plate 1, and a spring 29 is interposed between the injection pot 28 and the lower surface of the fixed die plate 1, so that the injection pot 28 is always is adapted to be biased downward. Note that the plunger 24 and injection pot 28 constitute a material supply device.

Next, the molding action of the molding machine configured as above will be explained.

In the mold opening state shown in FIG.
1 is regulated by the medium-sized positioning stopper 17, and the medium-sized holding plate 21 is in the lowest position, and both upper and lower engaging portions 9, 8 is connecting plate 1
The movable die plate 4 is engaged with the upper surface of the die plate 5 and the upper surface of the upper mold holding plate 10, respectively, and is at the lowest position. Also, the injection pot 28 is urged downward by the spring 9 and is at the lowest position.

When the piston rod 3a of the mold clamping cylinder 3 rises from this mold opening state, as shown in FIG.
The movable die plate 4 rises and the lower die 5 becomes the middle die 23.
overlap. At this time, the connecting rod 7 erected and fixed on the movable die plate 4 rises through the insertion hole 11 of the upper die holding plate 10 and the insertion hole 16 of the connecting plate 15.

When the piston rod 3a of the mold clamping cylinder 3 further rises from the state shown in FIG. 4, as the movable die plate 4 rises, the middle mold holding plate 21 is lifted by the lower mold 5, and the middle mold 23 is lifted. It overlaps the upper mold 13. When the medium holding plate 21 rises, the connecting plate 15 rises together with the connecting rod 7 on the movable die plate 4 via the connecting rod 18.

When the movable die plate 4 further rises from the state shown in FIG. 5, the upper mold holding plate 10 is lifted by the lower mold 5 via the middle mold holding plate 21, and the upper mold holding plate 10 The rubber material 14 on the upper mold 13 is inserted into the injection pot 28 while overlapping the injection pot 28 . At this time, since the medium-sized holding plate 21 also rises, the connecting plate 15 rises together with the connecting rod 7 on the movable die plate 4 via the connecting rod 18. Note that the rubber material 14 may be placed in the injection pot 28, as shown in phantom lines in FIG.

When the movable die plate 4 further rises from the state shown in FIG. 6, the injection pot 28 is moved by the lower mold 5 together with the middle mold holding plate 21 and the upper mold holding plate 10 against the bias of the spring 29. It is lifted up and overlaps with the plunger 24. At this time, as the medium holding plate 21 rises, the connecting plate 15
is raised together with the connecting rod 7 on the movable die plate 4 via the connecting rod 18. In this mold closed state,
The plunger 24 enters the injection pot 28,
The rubber material 14 is heated by the hot plates 6, 25 and simultaneously compressed by the plunger 24, flowing and flowing into the cavity.

After the molding is completed, when the piston rod 3a of the mold clamping cylinder 3 descends, as shown in FIG. The injection pot 28 is lowered by the force of the spring 29 following the lowering of the lower mold 5. At this time, as the medium holding plate 21 descends, the connecting plate 15 descends together with the connecting rod 7 on the movable die plate 4 via the connecting rod 18.

When the piston rod 3a of the mold clamping cylinder 3 further descends from the state shown in FIG. 8, as shown in FIG.
As the lower mold 5 descends, the middle mold holding plate 21 attaches to the lower mold 5 and descends. At this time, since the upper mold 13 usually does not have a cavity and only sprues and runners are formed, the middle mold 23 easily separates from the upper mold 13, but the upper mold 13 adheres to the injection pot 28 without separating from it. It remains as it is. Therefore, the upper mold holding plate 10 is lowered together with the injection pot 28 by the urging force of the spring 29 until the engaging portion 27a of the guide bar 27 and the upper surface of the fixed die plate 1 are engaged. When the hollow holding plate 21 descends, the connecting plate 15 connects to the movable die plate 4 via the connecting rod 18.
It descends together with the connecting rod 7 above.

When the movable die plate 4 further descends from the state shown in FIG. 9, the lower mold 5
The medium-sized holding plates 21 are lowered while remaining attached to each other, and the connecting plate 15 is lowered together with the connecting rod 7 on the movable die plate 4 via the connecting rod 18.
The engaging portion 8 of the connecting rod 7 comes into contact with the upper surface of the upper die holding plate 10 . Thereafter, the upper die holding plate 10 is pushed downward by the engaging portion 8 as the movable die plate 4 descends, is forcibly separated from the injection pot 28, and is lowered by its own weight as shown in FIG. It descends until it comes into contact with the upper die positioning stopper 12.

When the middle mold holding plate 21 descends together with the lower mold 5,
The connecting plate 15 is lowered together with the connecting rod 7 on the movable die plate 4 via the connecting rod 18, and the connecting plate 15 comes into contact with the medium-sized positioning stopper 17 on the fixed die plate 1, as shown in FIG. With this contact, the lowering of the middle mold holding plate 21 is stopped, and the lower mold 5 is separated from the middle mold 23 as the movable die plate 4 descends, resulting in the mold opening state shown in FIG. 12. In addition,
The molded product is held in a medium mold 23 and is automatically taken out.

As described above, in this embodiment, when the movable die plate 4 descends as the piston rod 3a of the mold clamping cylinder 3 descends when the mold is opened, the engaging portion of the connecting rod 7 moves downward as the movable die plate 4 descends. 8 and the upper mold holding plate 10, the upper mold holding plate 10 is forcibly separated from the injection pot 28 and lowered.
The upper mold holding plate 1 is moved by the upper mold positioning stopper 12.
Since the lowering limit of 0 is regulated, unlike the conventional example described above, there is no need for a hydraulic cylinder dedicated to opening the mold, which is used to separate the upper mold holding plate from the injection pot, and only the mold clamping cylinder 3 is required. They can also be separated.

Note that the present invention is not limited to the embodiment described above, and the following configuration is also possible.

(a) In the above-mentioned embodiment, a molding machine including an upper mold, a middle mold, and a lower mold was exemplified, but the present invention can also be applied to a molding machine having only upper and lower molds.
In this case, the medium-sized positioning stopper means 1
5, 17, and 18 are not required.

(b) In the embodiment described above, the upper mold holding plate 10 is connected to the connecting rod 7 which is fixedly erected on the movable die plate 4.
An engaging portion 8 is formed for forcibly lowering the die plate 4, but the position and structure of the engaging portion 8 may be changed arbitrarily as long as the upper mold holding plate 10 can be forcibly lowered in conjunction with the lowering of the movable die plate 4. Can be changed.

(c) In the above-described embodiment, the upper die positioning stopper 12 that regulates the lowering limit of the upper die holding plate 10 is erected and fixed on the frame 2.
Its position and structure can be changed as desired, such as by suspending it.

(d) In the above-described embodiment, the medium-sized positioning stopper means for regulating the lowering limit of the medium-sized holding plate 21 is composed of the connecting plate 15, the medium-sized positioning stopper 17, and the connecting rod 18.
Also, the medium-sized positioning stopper 17 is eliminated and an engaging part is provided at the upper end of the connecting rod 18, and this engaging part is engaged with the upper surface of the fixed die plate 1,
Also, a connecting plate 15, a medium-sized positioning stopper 17
11 and 12 in place of the connecting rod 18.
A medium-sized positioning stopper 17 may be erected and fixed on the frame 2 as shown by imaginary lines in the figure.

Effects According to the present invention described in detail above, unlike the conventional example, the upper mold holding plate 10 is separated only by the mold clamping device 3 for operating the movable die plate 4, without using a hydraulic cylinder exclusively for mold opening. This eliminates the need for a hydraulic valve or electric control circuit associated with a hydraulic cylinder dedicated to opening the mold, which has the effect of simplifying the structure of the machine and the maintenance and inspection of the machine.

[Brief explanation of the drawing]

Fig. 1 and Fig. 2 show a conventional example, Fig. 1 is a front view showing the molding machine in a closed state, Fig. 2 is a front view showing the mold in an open state, and Figs. 3 to 12 are main views. One embodiment of the invention is shown, with FIG. 3 being a front view showing the mold in an open state, FIG. 4 being a front view showing a state in which the lower mold and the middle mold are overlapped as the movable die plate rises, and FIG. A front view showing a state in which the lower die, middle die, and upper die are stacked on top of each other as the movable die plate rises; FIG. Fig. 7 is a front view showing the mold closed state, Fig. 8 is a front view showing the plunger coming out of the injection pot as the movable die plate descends, Fig. 9 is a front view showing the movable die plate FIG. 10 is a front view showing a state in which the upper mold and middle mold are separated as the die is lowered, and FIG. 10 is a front view showing a state in which the engaging portion of the connecting rod on the movable die plate is engaged with the upper mold holding plate. , Fig. 11 is a front view showing a state where the upper mold is forcibly separated from the injection pot due to this engagement and descended, and the lowering limit is regulated by the upper mold positioning stopper, and Fig. 12 is a front view showing the middle mold holding state. FIG. 7 is a front view showing the mold opening state in which the lower limit of the plate is regulated by the middle mold positioning stopper and the lower mold is separated from the middle mold. Fixed die plate 1, mold clamping cylinder 3, piston rod 3a, movable die plate 4, lower mold 5,
Connecting rod 7, engaging portion 8, upper die holding plate 10, upper die positioning stopper 12, upper die 13, connecting plate 15, middle die positioning stopper 17, connecting rod 18, middle die holding plate 21, middle die 23, plunger 24, injection Pot28.

Claims (1)

[Claims] 1. A fixed die plate 1, a movable die plate 4 to which a lower mold 5 is attached, a mold clamping device 3 that operates the movable die plate 4, and a space between the fixed die plate 1 and the movable die plate 4. In a molding machine equipped with an upper mold holding plate 10 that is movable at the same time as the upper and lower molds 13 and 5, and material supply devices 24 and 28 that fill the cavities in the molds with material such as rubber when the molds are closed, when the molds are opened. , engaging means 7 and 8 are provided which engage with the upper die holding plate 10 so as to forcibly lower the upper die holding plate 10 as the movable die plate 4 descends, and a lowering limit of the upper die holding plate 10 is provided. A mold opening device for a molding machine, characterized in that an upper mold positioning stopper means 12 is provided for regulating the upper mold positioning stopper means 12. 2. A fixed die plate 1, a movable die plate 4 to which a lower mold 5 is attached, a mold clamping device 3 that operates the movable die plate 4, and an upper mold movable between the fixed die plate 1 and the movable die plate 4. Holding plate 10, medium holding plate 21, and both upper and lower molds 13, 5
In a molding machine equipped with material supply devices 24 and 28 that fill the cavity, etc., with material when the mold is closed, the upper mold holding plate 10 is forcibly lowered as the movable die plate 4 is lowered when the mold is opened. Engagement means 7 and 8 are provided to engage with the upper die holding plate 10 so as to hold the upper die holding plate 10 and the middle die holding plate 2.
Upper mold positioning stopper means 12 and middle mold positioning stopper means 15, 1 regulating the lowering limit of 1.
7, 18. A mold opening device for a molding machine, characterized in that a mold opening device is provided.