JP2511111B2 - Mold thickness adjusting device - Google Patents

Description

TECHNICAL FIELD The present invention relates to a mold thickness adjusting device applied to an injection molding machine or the like.

(Prior Art) FIG. 6 shows a conventional mold clamping device, 60 is a support frame, and a fixed mold 62 is provided on one end of the support frame 60.
The fixed die plate 64 with the fixed die plate 64 attached thereto is fixed, and the movable die plate 68 having the movable die 66 attached thereto is slidably mounted on the other end of the support frame 60 so as to face the fixed die plate 64. ing. The fixed die plate 64 is provided with a plurality (four in this example) of hydraulic cylinders 70, and the moving die plates 68 of the internal pistons 72 of these hydraulic cylinders 70 are provided.
Tie bars 74 are respectively extended from the side surface toward the moving die plate 68. Also, on one side of the fixed die plate 64,
Fix the boost cylinder 76, this boost cylinder 76
The tip portion of the rod 80 connected to the internal piston 78 is appropriately fixed to one side portion of the moving die plate 68.

On the other hand, a guide rod 82 having a diameter smaller than that of the tie bar 74 is provided as a guide member at the tip of the tie bar 74. Therefore, the moving die plate 68 is provided with an insertion hole 84 through which the tie bar 74 is inserted, and on the side surface of the moving die plate 68 opposite to the surface on which the moving die 66 is attached, the moving die plate 68 has a substantially axial center of the insertion hole 84. A half nut 86 that moves in a right angle direction is provided. Also, a step portion is formed adjacent to the half nut 86, through which a guide rod 82 protruding from the tip portion of the tie bar 74 is inserted, and which is formed at a boundary portion between the guide rod 82 and the tip portion of the tie bar 74. Providing a stopper 90 that can lock 88,
This is appropriately fixed to the moving die plate 68. Also,
A screw portion 92 that meshes with the half nut 86 is engraved on the outer periphery of the tip portion of the tie bar 74. Further, if necessary, each tie bar is provided on the tip of the guide rod 82 during mold clamping operation.
The connecting member 94 may be coupled for the purpose of synchronizing the movement of the 74.

In the mold clamping device in the above-described conventional example configured in this manner, when the mold is closed, one oil chamber 96 of the boost cylinder 76 is
By supplying pressure oil to the movable die plate 68, the movable die plate 68 is moved to the fixed die plate 64 side. At this time, the tie bar 74
The guide rod 82 projecting from the tip portion moves while sliding on the stopper 90, and the tip portion of the tie bar 74 is smoothly inserted into the insertion hole 84 of the moving die plate 68. Then, immediately before the mold closing of the fixed mold 62 and the moving mold 66 is completed,
The tip portion of the tie bar 74, that is, the step portion 88 formed at the boundary portion with the guide rod 82 is locked to the stopper 90 (FIG. 7).
At this time, if the half nut 86 provided on the moving die plate 68 is moved by the moving means 98 in a direction substantially perpendicular to the axial center of the insertion hole 84, this can be engaged with the screw portion 92 formed on the tie bar 74.

As a result, the tie bar 74 can achieve the fixed connection with the moving die plate 68. Then fixed die plate
When pressure oil is supplied to one oil chamber 100 of the hydraulic cylinder 70 provided in 64, the moving die plate 68 is moved to the fixed die plate 64 side by directly moving the tie bar 74, and is moved with the fixed die 62. Clamping with the mold 66 can be achieved.

Further, when the die is replaced, the joint fixing position of the moving die plate 68 with respect to the tie bar 74 is adjusted according to the thickness of the die, that is, in order to perform so-called die thickness adjustment, by changing the operating position of the stopper 90, Can be realized. For example, as shown in FIG. 8, it is possible to configure a stopper as a mold thickness adjusting means. The example shown in FIG. 8 is characterized in that a stopper piece 102 is provided on the guide rod 82 so as to be movable back and forth in a direction substantially perpendicular to the axis thereof.

In this case, the stopper piece 102 has a substantially semicircular cutout 104 that can be slidably contacted with the guide rod 82, and the upper end of the stopper piece 102 is fixed to the piston rod 110 of the pressure cylinder 108 fixed to the support frame 106. Then, a plurality of the stopper pieces 102 configured in this way are installed on the common support frame body 106 at predetermined intervals in the axial direction of the guide rod 82, and the support frame body 106 is attached to the movable die plate 68. By arranging the plurality of stopper pieces 102 with respect to the guide rod 82 in this manner, one of the stopper pieces 102 is selected according to the thickness of the mold.
By advancing with respect to the guide rod 82 by an automatic control operation, the tip portion of the tie bar 74 can be properly positioned.

(Problems to be Solved by the Invention) However, in the mold thickness adjusting apparatus shown in FIG. 8, a plurality of stopper pieces 102, which are installed at a predetermined interval apart from each other, are configured and arranged with respect to the guide rod 82 to adjust the thickness of the mold. Accordingly, one of the stopper pieces 102 is guided by the guide rod 82 by the automatic control device.
The front end of the tie bar 74 is positioned by moving the tie bar 74 forward. Therefore, even if this is sufficient when the mold is changed by a predetermined size, this method alone cannot cope with arbitrary mold thickness. Further, if it is attempted to cope with a case where the die thickness changes in a wide range, there is a problem that a large number of stopper pieces are required.

The present invention has been proposed to solve the above conventional problems.

(Means for Solving the Problem) Therefore, according to the present invention, a fixed die plate that holds a fixed die, a movable die plate that holds a movable die, and the movable die plate are moved backward with respect to the fixed die plate. And a tie bar for fastening the fixed die plate and the fixed die plate after the movable die plate approaches the fixed die plate and the fixed die and the moving die are closed. The tie bar is fixed to the movable die plate, has a long threaded portion on the side opposite to the fixed end thereof, and a half nut that can be opened and closed substantially at right angles to the tie bar axis on the anti-die mounting surface side of the fixed die plate. The half nut is urged to come into pressure contact with the tip of the ram that constitutes the insertion hole of the tie bar mounted on the fixed die plate, and at the same time the end surface of the ram rotates. Is pressed against the stopper surface of the sprocket that moves forward and backward,
The meshing position of the half nut is adjusted by rotating the sprocket and adjusting the position of the stopper surface of the sprocket. This is a means for solving the problem.

(Function) A screw is provided at the tip of the tie bar fixed to the moving die plate, and the screw has a sufficient length to engage with the half nut even if the die thickness changes, and it is used as the position of this half nut. Since the sprocket has internal threads, it can move in the axial direction when rotated, and the position of the half nut can be adjusted. Position control can be easily performed by automatically controlling the rotation of the sprocket according to the shift of the meshing position between the tie bar screw and the half nut screw caused by the change of the die thickness.

(Embodiment) The present invention will be described in detail below based on an embodiment of the drawings. FIG. 1 shows an embodiment of the device of the present invention, in which 150 is a base for mounting and fixing the main mold clamping device, A fixed die plate 154 for mounting a fixed mold 152 is fixed to one end of the base 150. Reference numeral 158 denotes a movable die plate, a movable die 156 is attached to the fixed die plate 154 side, and a slide shoe 159 is integrally attached to the legs of the movable die 154, and a guide rail 151 provided on the base 150. It is mounted so that it can move forward and backward. The moving die plate 15
The guide portion 8 may be a sliding slide, a rolling guide, or may be floated by air or magnetic force.

Further, hydraulic cylinders 160 that generate a mold clamping force after mold closing are formed at the four corners of the fixed die plate 154, and the hydraulic cylinders 160 are provided with oil chambers 161A and 161B inside by sandwiching a ram 162 as described later. Has been. As shown in the enlarged view of FIG. 2, the ram 162 has a multi-tiered outer circumference with large, medium and small diameters.
An insertion hole 174 of the tie bar 164 is formed through the axial center,
When the mold clamping pressure is increased, pressure oil is sent to the one oil chamber 161A to move it to the right in FIG. 1, and the tip portion 163 thereof is brought into contact with the half nut 180, and the half nut 180 is attached to the tie bar.
The half nut 180 is further pushed to the right in the state of being meshed with 164 to generate a mold clamping force. One end of the tie bar 164 is fixed to the moving die plate 158 by a nut 165, and a screw portion 172 is provided at the tip of the tie bar 164 over a predetermined length.
The screw portion 172 meshes with the half nut 180 provided on the back side of the fixed die plate 154 during mold clamping.

166 is a fixed die plate 154 or a movable die plate 158.
Is a mold opening / closing cylinder that moves the moving die plate 158 forward and backward, and the tip of the rod 170 of the mold opening / closing cylinder 166 is fixed to the moving die plate 158 or the fixed die plate 154. 175 and 176 are packing retainers fixedly provided in front of and behind the portion of the fixed die plate 154 that constitutes the mold clamping cylinder. The guide bar 177 is fixed. A half nut 180, which is a nut divided into two and is opposed to the guide bar 177, is slidably supported via a bracket 178. The half nut 180 is constantly rammed by a spring 179.
The tip portion 163 of the 162 is urged to come into pressure contact. At the same time, the end surface 163a of the ram 162 is also the stopper surface of the sprocket 190.
Pressed against 190a. Half nut 180 is bracket 1
The guide bar 181 fixed to the 78 can be opened and closed to the left and right by an opening / closing mechanism (not shown), and is closed during mold clamping to engage with the threaded portion 172 of the tie bar 164.

A sprocket 190 having an internal thread is engaged with a screw rod 191 attached to the packing retainer 176. It moves back and forth in the direction indicated by the arrow in the figure. That is, half nut 18
By adjusting the position of 0, the meshing position of the screw thread can be adjusted.

Next, the operation will be described. When the die is changed so that the die thickness is changed, it is necessary to adjust the die thickness (correction of screw engagement). The operation procedure in this case is as follows. is there. First, turn on the mold thickness setting switch (not shown).

Next, pressure oil is sent to the oil chamber 168A of the mold opening / closing cylinder 166 to bring the mold into close contact (the fixed mold 152 and the movable mold 156 are engaged with each other ... Fig. 4). A pulse motor or the like is used to rotate the sprocket 190, and the thickness of the mold when the mold is closed is automatically measured by a linear scale (not shown). The amount is calculated by the computer to calculate the correction amount.

Next, pressure oil is sent to the oil chamber 161A of the ram 162 (low pressure at this time) to advance the ram 162, and the stopper surface of the sprocket 190 is stopped.
The contact with 190a is cut off, and only the correction amount is rotated in any direction (Fig. 3).

Next, pressure oil is sent to the oil chamber 161B of the ram 162 to retract the ram 162, and the ram 162 is applied to the stopper surface 190a of the sprocket 190 to stop. In this case, since the half nut 180 is constantly pressed against the ram 162 by the spring 179, the position of the half nut 180 is determined by the position of the sprocket 190, and the mold thickness adjustment is completed.

(Effects of the Invention) Since the present invention is configured as described in detail above, the tie bar screw is cut long so as to correspond to the mold thickness change range, and a slight deviation of the peak and valley from the half nut screw is corrected. Only with this, it is possible to engage at any position. Moreover, since the meshing position of the tie bar and the half nut is adjusted by rotating the sprocket, there is no variation and it can be done at the same time. On the other hand, the correction amount is naturally determined if the thickness of the mold is known, and therefore, the thickness of the mold can be read and the sprocket of the mold thickness adjusting device can be fully automated.

[Brief description of drawings]

FIG. 1 is a front sectional view of a mold thickness adjusting apparatus showing an embodiment of the present invention, FIG. 2 is a detailed view of a main part of the mold thickness adjusting apparatus of FIG. 1, and FIG. 3 is a main part of FIG. Detailed view, FIG. 4 is a front sectional view showing a different operating state from FIG. 1, FIG. 5 is a view taken in the direction of arrow C of FIG. 4, and FIG. 6 is a plan sectional view showing an example of a conventional mold clamping device. Fig. 7 and Fig. 7 are plan sectional views in which the operating state is different from Fig. 6,
FIG. 8 is a side sectional view of a mold thickness adjusting device used in the mold clamping device of FIGS. 6 and 7. Description of main parts of figure 154 …… Fixed die plate 158 …… Moveable die plate 164 …… Tie bar 166 …… Mold opening / closing cylinder 172 …… Screw part 180 …… Half nut 190 …… Sprocket 191 …… Screw rod

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Mitsuro Iwamoto No. 1 Takamichi, Iwatsuka-cho, Nakamura-ku, Nagoya, Aichi Prefecture Mitsubishi Heavy Industries, Ltd. Nagoya Machinery Works (72) Saburo Fujita Iwatsuka, Nakamura-ku, Nagoya, Aichi 1st high street in the town area Mitsubishi Heavy Industries, Ltd. Nagoya Machinery Works

Claims (1)

(57) [Claims] 1. A fixed die plate for holding a fixed mold,
A moving die plate for holding the moving die, a means for moving the moving die plate backward with respect to the fixed die plate, and the moving die plate approaching the fixed die plate to close the fixed die and the moving die. And a fixed die plate and a tie bar that is fixedly coupled with the fixed die plate to perform mold clamping.The tie bar is fixed to the movable die plate and has a long screw portion on the opposite side of the fixed end. A half nut that can be opened and closed almost at right angles to the tie bar axis is provided on the side of the die plate opposite to the die mounting surface.
The half nut is urged to press against the tip of the ram that constitutes the insertion hole of the tie bar attached to the fixed die plate, and at the same time, the end surface of the ram is pressed against the stopper surface of the sprocket that moves forward and backward by rotating. The half-nut engagement position is adjusted by rotating the sprocket and adjusting the position of the stopper surface.