JP3274932B2 - Mold clamping device for blow molding machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mold clamping device for a hollow molding machine, and more particularly, to a mold-opening / closing operation by using a motor-driven toggle mechanism through an additional mold clamping by a motor, so that a molded article is not stained smoothly. It relates to a new improvement for performing high-precision mold clamping.

[0002]

2. Description of the Related Art As a conventional mold clamping device for a hollow molding machine of this type, for example, a structure disclosed in Japanese Patent Application Laid-Open No. 6-869 shown in FIGS. 4 and 5 can be mentioned. . That is, what is indicated by reference numeral 1 in FIGS. 4 and 5 is a mold that can be opened and closed and includes a first mold part 2 and a second mold part 3. Parison 6 hanging from crosshead 5 of machine 4
Is configured to be supplied.

The second mold part 3 is connected to a toggle mechanism 9 comprising a pair of bendable first and second toggle pieces 7 and 8 via a second mold holder 10 and a first clevis 7a. A guide block 12 that holds a shaft support 11 to which the toggle pieces 7 and 8 are connected in a freely bendable manner is configured to be guided by a pair of center positioning guide bars 13 and 14.

The guide block 12 is configured to be able to reciprocate in the axial direction by a feed screw 16 such as a ball screw which is rotated by an electric motor 15, and the first die 2 is provided with a first die holder 17. Is provided.

[0005] A pair of rods 1 is mounted on a rear plate 18 connected to the second toggle piece 8 via a second clevis 8a.
9 and 20 are connected, and each rod 19 and 20 is fixedly connected to a holder 21 connected to the first mold holder 17, and this rod 19 is connected to the first mold holder 10.
Operatively penetrates, and the rear plate 18, the rods 19 and 20, and the connecting body 21 constitute a mold opening / closing interlocking mechanism 50 for the mold 1.

Accordingly, in the above-described configuration, the electric motor 1
5 to move the guide block 12 with the feed screw body 16, the toggle pieces 7, 8 become linear or bent along the positions shown by the dotted and solid lines as shown in FIG. In the case of (1), the mold holding bodies 10 and 17 move in the direction of joining with each other via the mold opening / closing interlocking mechanism 50, so that the mold sections 2 and 3 are closed. The mold parts 2 and 3 are opened in reverse to the above.

[0007]

Since the conventional mold clamping device of the blow molding machine is constituted as described above, there are the following problems. That is, when the mold is clamped using only the toggle mechanism, the error in the thickness of the mold is reduced by 200 to 3 times.
If it is not less than 00 μm, the mold clamping force is not sufficient. Therefore, in order to increase the accuracy of the thickness of the mold, the production cost of the mold has been high. In addition, when adjusting the thickness of the mold, the working time is long. Further, in the mold clamping using only the toggle mechanism, a force acts in the direction of arrow C in FIG. 2 and the mold gradually closes in the direction of arrow D as the mold closes. In some cases, the left and right swingback of the specific mold occurs, and a difference in the mating surfaces of the molds occurs. In addition, the guide pins of the mold were easily damaged and abrasion was also likely to occur.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems. In particular, by performing mold opening and closing via a motor-driven toggle mechanism through additional mold clamping by a motor, there is no contamination of molded products. An object of the present invention is to provide a mold clamping device for a hollow molding machine that performs smooth and high-precision mold clamping.

[0009]

According to the present invention, a mold clamping apparatus for a blow molding machine includes a parison hanging from a crosshead.
In a mold clamping device of a hollow molding machine which is held by a mold to be opened / closed and clamped through a mold opening / closing interlocking mechanism to obtain a hollow molded product, a rear plate of the mold opening / closing interlocking mechanism and the mold are provided. A toggle mechanism provided between the second mold parts, a guide block provided on a shaft support of the toggle mechanism,
A feed screw body screwed into the guide block, an electric motor for rotating the feed screw body, a plurality of guide bars for operably holding a second clevis of the toggle mechanism on the rear plate, A motor provided on a rear plate; and a contact / separation coupling part for causing the second clevis to move toward / separate from the rear plate by the motor. The metal is provided via the toggle mechanism and the contact / separation coupling part. In this configuration, the mold is clamped.

[0010] More specifically, the contact / separation coupling portion is configured by a nut provided on the second clevis, and a screw body connected to the motor and screwed to the nut.

More specifically, the contact / separation coupling portion includes a nut provided on the second clevis, and a screw body connected to the motor via a pulley and a belt and screwed to the nut. Configuration.

[0012]

In the mold clamping device for a blow molding machine according to the present invention, the guide block moves in the front-rear direction by rotating the feed screw by the electric motor, and in conjunction with this, each toggle piece of the toggle mechanism is linear or It becomes bent. Therefore,
After opening the mold with this toggle mechanism bent, insert the parison hanging from the crosshead into the cavity,
When this toggle mechanism is linear, the mold is closed. In the above state, the second clevis is retracted in the direction of arrow A by rotating the motor attached to the rear plate.
The mold has a slight gap. Next, rotate the motor attached to the rear plate to rotate the screw body,
By pressing the second clevis in the direction of arrow B via the nut, the mold is completely closed and the mold is completely clamped. When the mold is opened, the motor is rotated to pull the second clevis in the direction of arrow A, and then each of the toggle pieces of the toggle mechanism is bent into a rectangular shape from a horizontal straight line to form the mold. Opening takes place.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a mold clamping device for a blow molding machine according to the present invention will be described below in detail with reference to the drawings. The same or equivalent parts as those in the conventional example will be described using the same reference numerals. That is, what is indicated by reference numeral 1 in FIGS. 1 and 2 is a mold that can be opened and closed and includes a first mold part 2 and a second mold part 3. Parison 6 hanging from crosshead 5 of machine 4
Is configured to be supplied.

The second mold part 3 is connected to a toggle mechanism 9 comprising a pair of bendable first and second toggle pieces 7, 8 via a second mold holder 10 and a first clevis 7a. A guide block 12 that holds a shaft support 11 to which the toggle pieces 7 and 8 are connected in a freely bendable manner is configured to be guided by a pair of center positioning guide bars 13 and 14.

The guide block 12 is configured to be able to reciprocate in the axial direction by a feed screw 16 such as a ball screw which is rotated by an electric motor 15, and the first die 2 is provided with a first die holder 17. Is provided.

A pair of rods 19, 20 are connected to a rear plate 18, which is connected to the second toggle piece 8 via a second clevis 8a and a plurality of guide bars 30, and each of the rods 19, 20 is connected to the first rod 19, 20. The rod 19 is fixedly connected to a holding body 21 connected to the mold holding body 17, and the rod 19 operatively penetrates the first mold holding body 10.
The rear plate 18, the rods 19, 20 and the connector 21 constitute a mold opening / closing interlocking mechanism 50 for the mold 1.

Each guide bar 30 provided on the second clevis 8a is slidably inserted into a guide bush 31 of the rear plate 18, and a nut 32 is provided on the second clevis 8a. I have. The rear plate 18 is provided with a speed reducer 34 and a motor 35 via a support 33, and a thrust bearing 36 provided in the rear plate 18 is provided with a screw body 37 screwed to the nut 32. The screw body 3 is provided rotatably.
Reference numeral 7 is connected to a shaft 34a of the speed reducer 34 via a coupling 39 having a key 38. Therefore, the nut 32 and the screw body 37 constitute a contact / separation coupling part 100 for making / leaving the second clevis 8a to approach / separate from / to the rear plate 18. Note that the motor 35 is used without using the coupling 39 and the speed reducer 34.
And the screw body 37 can be directly connected.

Next, a case where the mold 1 is clamped in the above-described configuration will be described. First, the guide block 1 is rotated by rotating the feed screw body 16 by the electric motor 15.
2 moves in the front-rear direction, and in conjunction with this, each toggle piece 7, 8 of the toggle mechanism 9 becomes linear or bent. Therefore,
After the toggle mechanism 9 is bent and the mold 1 is opened, the parison 6 hanging from the crosshead 5 is inserted into the cavity 1a, and then the toggle mechanism 9 is straightened.
Is closed. In the above-described state, since the second clevis 8a is retracted in the direction of arrow A by rotating the motor 35 attached to the rear plate 18, the mold 1 is not in a completely clamped state but has a slight gap. I have. Next, the motor 35 attached to the rear plate 18 is rotated to
By rotating the 7 and pushing the second clevis 8a in the direction of arrow B via the nut 32, the mold 1 is completely closed, and the mold is completely clamped. When the mold 1 is to be opened, the motor 35 is rotated to pull the second clevis 8a in the direction of arrow A, and then each of the toggle pieces 7, 8 of the toggle mechanism 9 is bent from a horizontal straight line into a V-shape. Then, the mold 1 is opened.

The structure shown in FIG. 3 shows another embodiment of the connecting / disconnecting portion 100, and the screw 37
Is connected via a belt 62 to a second pulley 61 provided on a motor shaft 35a of a motor 35 provided at a position separated from the rear plate 18, and the nut 32, Screw body 37, each pulley 6
0, 61 and the belt 62,
0. That is, since the pulleys 60 and 61 and the belt 62 are used instead of the coupling 39 and the speed reducer 34 in FIGS. 1 and 2, the length of the mold clamping device can be reduced.

[0020]

According to the present invention, a mold clamping device for a blow molding machine is provided.
With the above configuration, the following effects can be obtained. That is, since the mold can be opened and closed by an electric motor without using hydraulic pressure, a high yield can be obtained without the molded product being stained with oil. In addition, the motor can be opened and closed at an arbitrary speed and stopped at an arbitrary position by program control of the electric motor, so that a safe mold opening and closing without malfunction can be obtained. Further, due to the electric motor and the toggle configuration, it is possible to achieve significant cost reduction, energy saving, and space saving as compared with the conventional hydraulic control configuration. Further, the detection of the mold clamping force can be electrically confirmed by the load cell. Also, memorize the mold opening and closing speed,
Easy reproducibility of good data can be obtained. Further, since the mold is opened and closed by the toggle mechanism and the feed screw body, smooth operation by the guide block becomes possible, and further space saving can be obtained by downsizing the electric motor. Further, since the mold can be smoothly opened and closed, the yield associated with the hollow molding can be greatly improved as compared with the conventional case. Further, after the high-speed mold closing with the toggle, the direct pressure mold clamping with the motor and the screw body is performed, so that the mold does not swing back and forth which occurs when only the toggle mold clamping is performed. Accordingly, there is no difference between the mating surfaces of the molds, so that the parting line of the molded product is not streaked (reduced), and the molding quality can be improved. In addition, since the mold is not clamped only by the toggle mechanism, but is additionally clamped using a motor and a screw body, there is no force to shift the mold sideways as in the conventional case, so damage to the guide pins and Even when wear is reduced and the thickness of the mold is slightly different, complete mold clamping can be performed without performing the conventional adjustment. Further, as another example of use, the motor 35 and the screw body (ball screw) 37 are first turned to adjust the mold to a position where the mold can be clamped, and then the toggle is moved in the horizontal direction from the V-shape to clamp the mold. You can also. In this way, the required mold clamping force can be obtained even if the molds have slightly different thicknesses, so that the mold and the second mold holder 10 and the first mold holder 17 can be provided. Useless work and working time for adjusting with shim is not required.

[Brief description of the drawings]

FIG. 1 is a front view showing a mold clamping device of a blow molding machine according to the present invention.

FIG. 2 is a plan view of FIG.

FIG. 3 is a configuration diagram of a main part showing another embodiment of FIG. 1;

FIG. 4 is a front view showing a conventional mold clamping device.

FIG. 5 is a plan view of FIG. 4;

[Explanation of symbols]

 Reference Signs List 1 mold 2 first mold section 3 second mold section 5 crosshead 6 parison 8a second clevis 9 toggle mechanism 11 shaft support section 12 guide block 15 motor 16 feed screw body 18 rear plate 32 nut 35 motor 37 screw body 50 Mold opening / closing interlocking mechanism 100

Claims (3)

(57) [Claims] 1. A parison hanging from a crosshead (5)
(6), in a mold clamping device of a hollow molding machine, wherein a mold (1) for opening and closing and clamping the mold via a mold opening / closing interlocking mechanism (50) to obtain a hollow molded product, Open / close interlock mechanism
The rear plate (18) of (50) and the second mold part (3) of the mold (1)
A toggle mechanism (9) provided therebetween, a guide block (12) provided on a shaft support (11) of the toggle mechanism (9), and a feed screw (16) screwed into the guide block (12). ), An electric motor (15) for rotating the feed screw body (16), and a second clevis (8a) of the toggle mechanism (9) with the rear plate (18).
A plurality of guide bars (30) for operably holding the
A motor (35) provided on the rear plate (18), and a contact / separation coupling part (100) for moving the second clevis (8a) toward and away from the rear plate (18) by the motor (35). ), Wherein the mold (1) is clamped through the toggle mechanism (9) and the contact / separation coupling part (100). 2. The contact / separation coupling part (100) is connected to a nut (32) provided on the second clevis (8a), and is connected to the motor (35) and screwed to the nut (32). Screw body to do (37)
The mold clamping device for a blow molding machine according to claim 1, wherein 3. The connecting / disconnecting portion (100) includes a nut (32) provided on the second clevis (8a), and a pulley (60, 61) and a belt (62) connected to the motor (35). The mold clamping device for a blow molding machine according to claim 1, further comprising a screw body (37) connected to the nut (32) and screwed into the nut (32).