JP3255016B2 - Toggle type clamping device for electric vertical injection 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 toggle type mold clamping apparatus for moving a movable plate with respect to a fixed plate in an electric vertical injection molding machine.

[0002]

2. Description of the Related Art A toggle type mold clamping device for an electric vertical injection molding machine has been proposed as shown in FIG.
200813). More specifically, the movable platen 3 is fixedly provided on the upper end of the tie bar 4 above the fixed platen 2 fixed to the machine body 1, and the end plate 5 is provided below the fixed platen 2 with the lower end of the tie bar 4. And the movable plate 3 is provided so as to be movable up and down with respect to the fixed plate 2 together with the movable plate 3.

[0003] The fixed platen 2 and the end plate 5
A pair of toggle links 41 and 42 are pivots 43 and 44, respectively.
Is mounted so that it can be turned up and down freely.
5 are connected to each other so as to be able to flex vertically. The toggle links 42, 42 have a bell crank shape and have nut bodies 46a, 46b at the lower ends. Nut body 46a, 4
Reference numerals 6b are oppositely threaded, and are screwed to mutually oppositely threaded screw portions 47a, 47b of a horizontal screw shaft 47, respectively.

The screw shaft 47 is rotatable in the circumferential direction, and is connected to a drive motor 48 via a required transmission mechanism 49. The screw shaft 47 is vertically supported by a transmission mechanism 49, and a drive motor 48 is provided on a guide table 50 so as to be movable in a direction perpendicular to the plane of FIG. Dies 7 and 8 are attached to the fixed platen 2 and the movable platen 3. Reference numeral 9 denotes an injection device.

In the above-described toggle type clamping device of the electric vertical injection molding machine, when the screw shaft 47 is rotated by the operation of the drive motor 48 to move the nut bodies 46a and 46b away from each other, the toggle link 41 is provided. , 42 extend linearly and lower the end plate 5, so that the movable platen 3 moves downward by clamping and the molds 7, 8 are clamped between the movable platen 3 and the fixed platen 2. At this time, the screw shaft 47 is connected to the toggle links 42, 42.
And the drive motor 48 is driven by the screw shaft 4.
7 moves on the guide table 50 in accordance with the rise.

[0006]

In the above-described toggle type clamping apparatus for the electric vertical injection molding machine, the drive motor 48 is connected to the screw shaft 4.
Although it is possible to eliminate the eccentric load that occurs when the screw shaft 47 is vertically connected to one end of the screw shaft 7, the transmission mechanism 49 and the like must be moved following the vertical movement of the screw shaft 47.
There is a problem that the structure becomes complicated. Further, since it is structurally difficult to increase the rotation angle of the bell crank-shaped toggle link 42, there is also a complaint that the opening and closing stroke of the movable platen 3 cannot be increased.

[0007]

According to a first aspect of the present invention, there is provided a toggle type clamping apparatus for an electric vertical injection molding machine, comprising: a fixed platen fixed to a machine body;
A movable plate is fixedly provided on the upper end of the tie bar,
In a vertical injection molding machine provided below the fixed plate so that an end plate is fixed to a lower end of the tie bar and is movable up and down with respect to the fixed plate together with the movable plate, The movable link is clamped and moved by extending the toggle link, which is connected to the end link with the toggle link so as to be able to bend up and down freely by the toggle pin, by moving the crosshead connected to the toggle link by the toggle piece in the vertical direction. A toggle mechanism is provided for moving a screw shaft, which is rotated in the circumferential direction by a drive motor fixed to a machine body or the like below the fixed plate, with its upper end pivotally supported by the fixed plate to stop axial movement. The crosshead was provided vertically and screwed to the screw shaft so as to be movable up and down.

The toggle link can be extended by moving the toggle pin closer to the screw shaft, or the toggle link can be extended by moving the toggle pin away from the screw shaft.

Further, the toggle piece may be connected to a free end of the toggle link pivotally attached to the end plate by a connecting pin by a connecting pin. Alternatively, the toggle piece may be pivotally connected to the fixed plate side. It is also possible to adopt a configuration in which a connecting pin is connected to an intermediate portion of the toggle link that is pivotally connected. Preferably, the screw shaft is a ball screw shaft or a roller screw shaft.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described based on embodiments with reference to the drawings. The basic structure of the main part of the vertical injection molding machine, such as the fixed platen, the movable platen and the end plate, is the same as that in FIG. 1 to 4, the left half shows the mold open state, and the right half shows the mold clamped state.

FIG. 1 shows an embodiment of the present invention. Reference numeral 11 denotes a toggle mechanism. The toggle mechanism 11
Toggle links 13, 13 attached to the lower surface of the fixed plate 2 so as to be pivotable up and down by a pivot 12, and an upper surface of the end plate 5 to be pivotally attached up and down by a pivot 14, and one end of the toggle link 13. a toggle link 16, 16 which are connected by a toggle pin 15, crosshead nut structure connecting the toggle piece 18 which is rotatably pivoted up and down mounting shaft 17 by a connecting pin 19 to the other end of the toggle link 16 20. Left and right two sets of toggle links 13, 16
Can be bent up and down. The pivot 14 of the end plate 5 is provided directly below the pivot 12 of the fixed platen 2.

Reference numeral 22 denotes a screw shaft. Screw shaft 22
Is located in the middle of the two sets of toggle links 13 and 16,
The upper end and the lower end are pivotally supported by the fixed platen 2 and the bearings 23 and 24 of the machine body 1, and are vertically provided so as to be rotatable in the circumferential direction with the movement in the axial direction being stopped. The screw shaft 22 is preferably a ball screw shaft or a roller screw shaft.

The crosshead 20 is guided by a plurality of guide rods 25 (only one is shown in FIG. 1) vertically fixed to the fixed platen 2 or the machine body 1, and is screwed to the screw shaft 22. Have been. Therefore, when the screw shaft 22 is rotated, the crosshead 20 moves up and down along the guide rod 25. Needless to say, the crosshead 20 is a ball nut, a roller nut or the like according to the type of the screw shaft 22.

A driven pulley 26 is attached to the lower end of the screw shaft 22 and is connected to a drive pulley 28 of a drive motor 27 such as a servo motor by a timing belt 29. The pulleys 26 and 28 and the belt 29 constitute a transmission mechanism 30 for transmitting the rotation of the drive motor 27 to the screw shaft 22, but the transmission mechanism 30 may use another transmission member such as a gear. . The drive motor 27 is fixed to the machine body 1.

The mounting positions of the pulley 26 and the drive motor 27 are not limited to those shown in FIG.
2 can be attached to the upper part of the screw shaft 22 as shown in FIG. 2, and the driving motor 27 can be fixed near the fixed platen 2 or to the fixed plate itself.

Although only one tie bar 4 is shown in FIG. 1, two or more (normally four) tie bars 4 are provided. Taiba 4
The lower end is screwed into an adjustment nut 32, and by rotating the adjustment nut 32, the distance between the movable platen 3 and the end plate 5 can be finely adjusted according to the thickness of the molds 7, 8. It has become.

Next, the operation of the toggle type mold clamping device of the electric vertical injection molding machine according to the present invention having the above-described structure will be described. When the drive motor 27 is operated from the mold opening state on the left side in FIG. 1 to rotate the screw shaft 22 and lower the crosshead 20, the toggle piece 18 pushes the inner end of the toggle link 16 downward. The reference numeral 13 turns the end plate 5 downward by rotating inward about the pivots 14 and 12 so that the toggle pin 15 approaches the screw shaft 22. As a result, the movable platen 3 moves downward with the mold together with the end plate 5, and the mold clamping is completed when the toggle links 13 and 16 extend linearly as shown in the right side of FIG.

When the driving motor 27 is operated to rotate the screw shaft 22 in the reverse direction in the mold clamping state on the right side of FIG. 1, the toggle links 16 and 13 are bent outward and the end plate 5 is raised. The movable platen 3 opens and moves upward.

In the above-mentioned toggle type mold clamping device, when the movable platen 3 is opened and closed by the operation of the toggle mechanism 11, there is no need to move the transmission mechanism 30 or the drive motor 27, so that the structure is simplified. . Therefore, a toggle-type mold clamping device that is less likely to fail and has high reliability can be manufactured at low cost. Further, since there is almost no structural restriction on the rotation angle of the toggle link 16, the rotation angle is increased and
Opening and closing stroke can be increased.

FIG. 3 shows another embodiment of the present invention. In the case of this mold clamping device, the toggle piece 18 is connected to an intermediate portion of the toggle link 13 by a connection pin 19, and the toggle links 13 and 16 bent inward by bringing the toggle pin 15 close to the screw shaft 22 are connected to the toggle pin 13. 15 is moved away from the screw shaft 22 so as to extend linearly. The pivot 14 of the end plate 5 is provided at a position directly below the pivot 12 of the fixed platen 2 or at a position slightly inward from the position directly below. Other structures and operations are the same as those of the mold clamping device of FIG.

FIG. 4 shows another embodiment of the present invention. In the case of this mold clamping device, the crosshead 20 is
It is arranged below. Other structures and operations are the same as those of the apparatus of FIG. 1, but the height can be reduced in this mold clamping apparatus.

Although the mold clamping device shown in the figures has a mechanism in which the crosshead 20 descends and clamps the mold, it is also possible to adopt a configuration in which the crosshead 20 is raised to clamp the mold. Either or both of the toggle links 13 and 16 may have a configuration in which two or more link units are pin-connected.

[0023]

As described above, in the toggle type mold clamping device of the electric vertical injection molding machine according to the first aspect, the movable plate is fixed to the upper end of the tie bar above the fixed plate fixed to the machine body. And vertical injection molding provided below the fixed plate, with an end plate fixed to the lower end of the tie bar and movable vertically with the movable plate with respect to the fixed plate. In the machine, between the fixed plate and the end plate, a toggle link mutually connected to be able to bend up and down freely by a toggle pin is extended by a vertical movement of a crosshead connected to the toggle link by a toggle piece. toggle mechanism is provided to clamping the movable plate, below the fixed platen, a screw is rotated in the circumferential direction by the driving movement motor shaft, it is pivotally supported to the upper end to the stationary platen
Te et disposed vertically stop the movement in the axial direction and, since the cross head to the threaded shaft there is a movably screwed configurations vertically, thereby opening and closing movement of the movable platen by rotating the screw shaft causing the drive motor and the transmission mechanism is fixed at a predetermined position
And the structure becomes simple. Therefore, a toggle-type mold clamping device which is less likely to break down and has high reliability can be manufactured at low cost. Further, there is almost no restriction on the rotation angle of the toggle link in terms of the structure, and therefore, the rotation angle of the toggle link is increased to increase the opening / closing stroke of the movable plate, thereby improving the workability of the mold clamping device. .

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of a toggle-type mold clamping device of an electric vertical injection molding machine according to the present invention.

FIG. 2 is a sectional view showing a modification of the mold clamping device of FIG.

FIG. 3 is a sectional view showing another embodiment of the present invention.

FIG. 4 is a sectional view showing another embodiment of the present invention.

FIG. 5 is a front view of a toggle-type mold clamping device of a conventional electric vertical injection molding machine.

[Description of Signs] 1 Machine body 2 Fixed board 3 Movable board 4 Tie bar 5 End plate 11 Toggle mechanism 12, 14 Axis 13, 16 Toggle link 15 Toggle pin 18 Toggle piece 19 Connection pin 20 Crosshead 22 Screw shaft 27 Drive motor 30 Transmission mechanism

──────────────────────────────────────────────────の Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B29C 45/64-45/68 B22D 17/26 B29C 33/20-33/22

Claims (6)

(57) [Claims] A movable plate fixed to an upper end of a tie bar provided above a fixed plate fixed to a machine body; and an end plate fixed to a lower end of the tie bar below the fixed plate. In a vertical injection molding machine provided so as to be movable up and down with respect to the fixed plate together with the movable plate, between the fixed plate and the end plate, a toggle pin is connected to be freely bent up and down by a toggle pin. A toggle mechanism for extending the movable link with the toggle link by extending the cross link connected to the toggle link by a toggle piece in the up-down direction and moving the movable plate by mold clamping is provided, below the fixed plate ,
Threaded shaft which is rotated in the circumferential direction by the driving movement motor,
The upper end is pivotally supported by the fixed plate to stop the axial movement and lead
Directly provided et been, movably screwed been possible electric vertical injection molding machine of the toggle type mold clamping apparatus, wherein said cross head is up and down the screw shaft. 2. The toggle type mold clamping device for an electric vertical injection molding machine according to claim 1, wherein the toggle link is configured to extend by moving the toggle pin closer to the screw shaft. 3. The toggle-type mold clamping device for an electric vertical injection molding machine according to claim 1, wherein the toggle link is configured to extend by moving the toggle pin away from the screw shaft. 4. The toggle piece according to claim 1, wherein the toggle piece is connected to the end plate by a connecting pin at a free end of the toggle link opposite to the toggle pin.
4. A toggle-type mold clamping device for an electric vertical injection molding machine according to 2 or 3. 5. The electric vertical injection molding according to claim 1, wherein the toggle piece is connected by a connecting pin to an intermediate portion of a toggle link pivotally connected to the fixed platen side by a pivot. Toggle clamping device of the machine. 6. A toggle-type mold clamping device for an electric vertical injection molding machine according to claim 1, wherein the screw shaft is a ball screw shaft or a roller screw shaft.