JPH08285B2 - Die height adjustment device - Google Patents

Description

TECHNICAL FIELD The present invention relates to a die height adjusting device, and more specifically,
For example, in a die casting machine or a plastic molding machine that is configured to displace a moving mold along a plurality of tie bars toward a fixed mold and then perform mold clamping under the action of a toggle mechanism, move the mold to each tie bar. By providing displacement means for the molds and selectively disengaging these displacement means with respect to one drive source, the die height amount for each tie bar between the molds can be individually adjusted. The present invention relates to a die height adjusting device that can obtain an optimum mold clamping force.

[Prior Art] Generally, in a die casting machine or a plastic molding machine, a moving mold is moved toward a fixed mold so that the molds come close to each other, and then the mold of the mold is operated under the action of a toggle mechanism. It is tightening. Here, the amount of displacement of the movable mold with respect to the fixed mold by the toggle mechanism is set to be constant, and in order to obtain a desired mold clamping force, the distance between the molds when the molds approach each other, that is, the toggle mechanism. Must be set so that the distance between the dies immediately before the action of becomes a predetermined amount. Here, the die-to-die distance is called a die height amount, and this die height amount needs to be appropriately adjusted in consideration of thermal expansion of the die due to casting heat, replacement of the die, and the like.

On the other hand, the movable die is configured to be displaced along the plurality of tie bars when adjusting the die height amount. In this case, the movable die is displaced toward the fixed die by rotating the nut gear screwed to each tie bar by one motor. The motor and the nut gear screwed to each tie bar are connected via a gear train or the like.

By the way, when the movable die is displaced toward the fixed die by such a mechanism, the nut gears screwed to the tie bars are simultaneously driven by one motor.
There is a possibility that the die height amount of the movable die for each tie bar cannot be individually adjusted, and the movable die cannot be joined to the fixed die in a desired state. For example, when the molds are brought close to each other and a mold clamping force is applied to the molds under the action of a toggle mechanism, when the movable molds are inclined and joined to the fixed molds, the mold clamping between the molds is performed. This causes the inconvenience that the distribution of force is not uniform. That is, unless a desired mold clamping force is applied to a predetermined portion between the molds, a burr is generated in a cast product, or the molten metal is melted when the molten metal is injected into the cavities defined between the molds. It can squirt out of the mold and cause a very dangerous situation.

Therefore, in such a die casting machine, if each tie bar is provided with a motor for driving a nut gear and each nut gear is configured to be rotated by an independent motor, the die height amount of the movable die is adjusted for each tie bar. Therefore, it is possible to obtain a desired mold clamping force regardless of the state of the mold. However, the structure becomes extremely complicated when configured in this way,
Further, a sensor or the like for detecting the amount of displacement of the mold according to the amount of rotation is required for each motor. Therefore, the cost of the entire apparatus rises, and the probability of invention such as a failure increases.

[Problems to be Solved by the Invention] The present invention has been made in order to overcome the above-mentioned inconveniences, in which a movable die is displaced toward a fixed die along a plurality of tie bars, and then, In a die-casting mechanism or a plastic molding machine that clamps the molds under the action of a toggle mechanism, each tie bar is provided with displacement means for the movable mold, and one displacement source is associated with each displacement means. By making it detachable, it is possible to individually adjust the die height amount of the moving die for each tie bar, and an optimal die clamping force can be obtained, and the die height is extremely simple in construction and there is no risk of failure. It is an object to provide an adjusting device.

[Means for Solving the Problem] In order to achieve the above-mentioned object, the present invention provides a structure between a movable mold that is displaced toward a fixed mold along a plurality of tie bars and the fixed mold. In a die height adjusting device for adjusting a die height amount, a drive source and a portion of the movable die corresponding to the tie bar, which is disposed on each of the tie bars, are displaced toward the fixed die under the action of the drive source. A plurality of displacing means, a plurality of driving force transmitting means for transmitting the driving force of the driving source to each of the displacing means, and a plurality of driving force transmitting means for each of the displacing means independently of each other. A plurality of engaging / disengaging means for releasing, a plurality of detecting means for detecting a physical quantity corresponding to the die height amount between the fixed die and the moving die for each of the tie bars, and a die height amount based on the physical quantity. Predetermined die height amount In order to adjust to, the engaging / disengaging means is actuated to selectively engage / disengage the driving force transmitting means with respect to each of the displacement means,
And a control unit that controls the drive of the drive source.

[Embodiment] Next, a preferred embodiment of the die height adjusting apparatus according to the present invention will be described in detail below with reference to the accompanying drawings.

1A and 1B, reference numeral 10 indicates a main body of a die casting machine equipped with a die height adjusting device according to the present invention. The main body portion 10 has a fixed die plate 14 on which a fixed die 12 is mounted, a movable die plate 18 on which a movable die 16 is mounted, and which moves toward the fixed die plate 14,
It includes a link housing 20 for displacing the movable die plate 18 toward the fixed die plate 14 by a predetermined amount.
The fixed die plate 14 has a fixed die 12 and a movable die 16
A hot water supply unit (22) for injecting molten metal into a cavity defined between is connected to the hot water supply unit (22).

The fixed die plate 14 has four corner portions 24a to 24d, and one end portion of each of the tie bars 26a to 26d arranged in parallel with each other at each of the corner portions 24a to 24d has a tie bar nut 35a.
Through 35d. The movable die plate 18 is slidably engaged with the middle portion of the tie bars 26a to 26d through the corner portions 28a to 28d. Further, threaded portions 30a to 30d are formed on the other end side of each tie bar 26a to 26d, and the link housing 20 is engaged with these threaded portions 30a to 30d via their corner portions 32a to 32d. To do.

Here, the link housing 20 and the movable die plate
18 is connected via a toggle mechanism 34. That is, the link member is provided at each corner 32a to 32d of the link housing 20.
One end of each of the link members 38a to 38d is pivotally attached to one end of each of the link members 36a to 36d, and each of the corners 28a to 28d of the movable die plate 18 has a length substantially equal to that of each of the link members 36a to 36d. Is pivotally attached. Then, these link members 36
The other end portions of a to 36d and 38a to 38d are rotatably connected to the respective one end portions of short link members 40a to 40d. On the other hand, a toggle driving cylinder 42 for driving the toggle mechanism 34 is attached to the center of the link housing 20, and a cylinder rod 44 constituting the cylinder 42 has a tip end portion of the link members 40a to 40d. Each other end is pivotally attached. The link housing 20 and the moving die plate
18 is directed toward the fixed die plate 14 through the toggle mechanism 34 and is integrally displaced.

As shown in FIG. 2, the link housing 20 includes a displacement mechanism 46 for displacing the link housing 20 and the movable die plate 18 toward the fixed die plate 14. That is, the link housing 20 has its corner 32
It engages with the threaded portions 30a to 30d of the tie bars 26a to 26d via nut gears 48a to 48d arranged on the a to 32d. In the link housing 20, a motor 50 as a drive source is mounted between the nut gears 48a and 48b. A drive gear 52 is engaged with the rotary drive shaft 51 of the motor 50, and the drive gear 52 and the nut gears 48a to 48d are connected via a plurality of gears.

That is, the drive gear 52 meshes with the gear 54,
A nut gear 48a is connected to 54 through a connecting gear 56a, and a nut gear 48b is connected through a connecting gear 56b. In this case, the connecting gears 56a and 56b are displaceable with respect to the nut gears 48a and 48b by being displaced in the arrow direction by the cylinders 58a and 58b mounted on the link housing 20. A large-diameter gear 60 that meshes with the gear 54 is attached to the outer peripheral portion of the toggle drive cylinder 42 at the center of the link housing 20, and the gear 60 has the same number of teeth as the gear 54. 62 mesh. The gear 62 is connected to the nut gear 48c via the connecting gear 56c and the nut gear 48d via the connecting gear 56b. here,
Like the connecting gears 56a and 56b, the connecting gears 56c and 56d are displaceable with respect to the nut gears 48c and 48d by being displaced in the arrow direction by the cylinders 58c and 58d.

FIG. 3 shows an example of the control circuit of the displacement mechanism 46. In this case, the cylinders 58a to 58d for displacing the connecting gears 56a to 56d are driven by the solenoid valves 64a to 64d. In addition, the toggle mechanism is changed from the state of FIG. 1b.
When the mold is clamped under the action of 34, the mold clamping force generated between the molds 12 and 16 is the load meter 66a attached to each tie bar 26a to 26d.
Through 66d. Further, the rotation amount of the motor 50 that displaces the link housing 20 and the movable die plate 18 toward the fixed die plate 14 is detected by the position sensor 68.

On the other hand, the solenoid valves 64a to 64d and the motor 50 are drive-controlled by a control unit 70 including a microprocessor or the like. That is, the control unit 70 uses the CPU 72, R
It consists of OM74, RAM76, I / O ports 78 and 80. The input / output port 78 receives a load signal corresponding to the mold clamping force detected by each load meter 66a to 66d via the interface 82, and outputs a drive signal to each solenoid valve 64a to 64d via the interface 84. . Further, the input / output port 80 receives a position signal as a rotation amount of the motor 50 from the position sensor 68 via the interface 86, and the motor via the interface 88.
The drive signal is output to 50. And these inputs and outputs are RO
It is controlled by the CPU 72 based on the control program stored in the M74 and the control data stored in the RAM 76.

The die casting machine provided with the die height adjusting device according to the present invention is basically constructed as described above. Next, its operation and effect will be explained.

Therefore, the procedure for adjusting the die height amount will be described based on the flowchart shown in FIG.

First, the motor 50 is driven under the action of the control unit 70 with the connecting gears 56a to 56d constituting the displacement mechanism 46 meshed with the nut gears 48a to 48d. That is, the RAM 7 of the control unit 70
6, the distance between the fixed die plate 14 and the movable die plate 18 immediately before the toggle mechanism 34 acts is shown in FIG.
The amount of rotation of the motor 50 required to achieve the die height amount H shown in FIG. 3 is stored in advance, and the drive signal corresponding to this amount of rotation is transmitted from the CPU 72 to the input / output port 80 and the interface 88 based on the control program stored in the ROM 74. Is output to the motor 50 via. Therefore, the motor 50 rotates the drive gear 52 based on the drive signal (STP1), and the nut gears 48a to 48d rotate via the gears 54, 60 and 62 connected to the drive gear 52 and the connection gears 56a to 56d. Be moved. In this case, the nut gears 48a to 48d mounted on the link housing 20 are the screw parts 30a to 48d provided on the tie bars 26a to 26d.
It is screwed to 30d. Therefore, the link housing 20
Moves toward the fixed die plate 14, and at the same time, the moving die plate 18 connected to the link housing 20 via the toggle mechanism 34 moves toward the fixed die plate 14.

On the other hand, the rotation amount of the motor 50 is detected by the position sensor 68, and the position signal from the position sensor 68 is transmitted from the input / output port 80 to the control unit 70 via the interface 86.
Input to CPU72. Therefore, the CPU 72 uses the position signal and RAM 7
When the rotation amount data of the motor 50 stored in advance in 6 is compared and it is detected that the motor 50 has rotated by a predetermined amount (STP2), the input / output port 80 rotates to the motor 50 via the interface 88. Output a stop signal (STP3). The state at this time is shown in FIG.

Next, the toggle drive cylinder 42 is driven from the state shown in FIG. 1b, and the cylinder rod 44 thereof is displaced in the direction of arrow a. In this case, the link members 40a to 40d are the link members 36a.
Through 36d and 38a through 38d, the tie bars 26a through 26
Press in the direction of d. Therefore, the movable die plate 18 is displaced in the direction of the arrow a by the link members 38a to 38d, and the mold clamping operation between the fixed mold 12 and the movable mold 16 is performed (STP4).

Here, the load meter 66a is attached to each of the tie bars 26a to 26d.
To 66d are attached, and these load meters 66a to 66d detect the mold clamping force at a predetermined portion between the molds 12 and 16 (STP5). Then, the mold clamping force detection signals from the load meters 66a to 66d are sent to the control unit 70 via the interface 82.
Input to I / O port 78 of. In this case, RA of the control unit 70
Data of the target mold clamping force for each of the tie bars 26a to 26d is stored in the M76 in advance. Therefore, the CPU 72 compares the target mold clamping force with the measured mold clamping force detected by the load meters 66a to 66d, and when they match (STP
6), the operation of adjusting the die height amount is completed, and then the hot water supply unit 22 is driven to inject the molten metal into the cavity defined between the fixed mold 12 and the movable mold 16.

On the other hand, when the target mold clamping force and the measured mold clamping force do not match, the toggle driving cylinder 42 is driven and the cylinder rod 44 thereof is displaced in the direction opposite to the arrow a direction, and the die 12,
The mold opening operation between 16 is performed (STP7). And again the first
The state shown in FIG.

Therefore, description will be given below assuming that the measured mold clamping force with respect to the target mold clamping force in each tie bar 26b to 26d is shown in the table.

In this case, since the target mold clamping force and the measured mold clamping force are different in the tie bar 26d, first, the connecting gears 56a to 56c other than the connecting gear 56d corresponding to the tie bar 26d are respectively connected to the nut gears 48a to 48c. Disengage from. That is, CPU72
Controls solenoid valves 64a through 64c from input / output port 78 through interface 84, which
58a to 58c are driven, the coupling gears 56a to 56c are displaced and disengaged from the nut gears 48a to 48c (STP8).

Then, the connection gears 56a to 56c are connected to the nut gears 48.
CPU7, when it is detected that it has been separated from a to 48c (STP9)
2 outputs a drive signal from the input / output port 80 to the motor 50 via the interface 88.

Here, when the rotation amount of the motor 50 required to obtain the unit mold clamping force is k, the measured mold clamping force C for the tie bar 26d is
The rotation amount α of the motor 50 required to match the target mold clamping force B with α is α = (B−C) · k (1). Therefore, the CPU 72 calculates the rotation amount α based on the equation (1), and outputs a drive signal corresponding to the rotation amount α to the motor 50.
Output to. The motor 50 is driven by the drive signal (STP10), and the drive gear 52 that engages with the rotary drive shaft 51 rotates. In this case, the drive gear 52 rotates only the nut gear 48d via the gears 54, 60, 62 and the connecting gear 56d.
Therefore, in the link housing 20, only the corner portion 32d to which the nut gear 48d is attached is displaced along the tie bar 26d. As a result, the corner portion 28d of the moving die plate 18 is displaced by a predetermined amount along the tie bar 26d via the link members 36d and 38d that form the toggle mechanism 34.

On the other hand, the position sensor 68 detects the rotation amount of the motor 50 and outputs the position signal via the interface 86 to the input / output port.
Supply to 80. When the control unit 70 compares the position signal input to the input / output port 80 with the rotation amount α of the motor 50 calculated based on the equation (1), and detects that the motor 50 has rotated by a predetermined amount. (STP11), a stop signal is output to the motor 50 to stop its operation (STP12). In this case, in the rotation amount data of the motor 50 stored in the RAM 76, only the rotation amount data regarding the tie bar 26d is corrected by the rotation amount α.

Next, the CPU 72 transfers the I / O port 78 to the interface 8
The solenoid valves 64a to 64c are controlled via 4 to drive the cylinders 58a to 58c. As a result, the connection gears 56a to 56c mesh with the nut gears 48a to 48c (STP13).
Therefore, when it is detected that the connecting gears 56a to 56d are engaged (STP14), the control unit 70 drives the toggle driving cylinder 42, and the mold clamping operation between the fixed mold 12 and the movable mold 16 is performed. (STP15). In this case, each of the load meters 66a to 66d measures the mold clamping force equal to the target mold clamping force. Next, the hot water supply unit 22 is driven, and the molten metal is injected into the cavity defined between the fixed mold 12 and the movable mold 16 to perform casting work.

In the above-described embodiment, the case where only the mold clamping force on the tie bar 26d is adjusted has been described.
It will be easily appreciated that the adjustment of the mold clamping force with respect to 26a to 26c can be similarly performed.

[Effects of the Invention] As described above, according to the present invention, the movable mold is displaced toward the fixed mold along the plurality of tie bars, and the mold is clamped between the molds under the action of the toggle mechanism. When performing the above, one drive source is configured to be engageable with and disengageable from each of the displacement means of the movable die provided in each of the tie bars. Therefore, it is possible to individually adjust the die height amount of the moving mold with respect to each tie bar, and therefore, it is possible to extremely easily obtain the optimum mold clamping force according to the shape of the mold and the like. Further, since the die height amount for each tie bar can be adjusted by one drive source and the adjustment amount can be detected by a single sensor connected to the drive source, the configuration is extremely simple and the occurrence rate of failures and the like can be reduced. The advantage is reduced.

Although the present invention has been described with reference to the preferred embodiments, the present invention is not limited to these embodiments, and various improvements and design changes can be made without departing from the scope of the present invention. Of course.

[Brief description of drawings]

1A and 1B are side explanatory views showing a state of a die in a main body of a die casting machine equipped with a die height adjusting device according to the present invention when the molds are separated from each other, and FIG. 2 is a die height adjusting device according to the present invention. FIG. 3 is a configuration block diagram showing an example of a control circuit of the die height adjusting apparatus according to the present invention, and FIG. 4 is a flowchart for explaining the operation of the die height adjusting apparatus according to the present invention. is there. 10 …… Main body, 12 …… Fixed die 14 …… Fixed die plate, 16 …… Movable die 18 …… Moveable die plate, 20 …… Link housing 26a-26d …… Tie bar, 34 …… Toggle mechanism 42 ...... Toggle drive cylinder 46 …… Displacement mechanism 48a to 48d …… Nut gear 50 …… Motor, 58a to 58d …… Cylinder 64a to 64d …… Solenoid valve 66a to 66d …… Load meter 68 …… Position sensor, 70… … Control unit

Claims (4)

[Claims] 1. A die height adjusting device for adjusting a die height amount between a fixed mold and a movable mold that is displaced toward a fixed mold along a plurality of tie bars, comprising: a drive source; and each of the tie bars. A plurality of displacing means for displacing a portion of the movable die corresponding to the tie bar toward the fixed die under the action of the drive source, and a driving force of the drive source for each of the displacements. A plurality of driving force transmitting means for transmitting to the respective means, a plurality of engaging / disengaging means for independently engaging / disengaging the respective driving force transmitting means with respect to the respective displacing means, the fixed mold and the movable metal. A plurality of detecting means for detecting a physical quantity corresponding to the die height amount between the mold and each of the tie bars, and in order to adjust each die height amount based on the physical amount to a predetermined die height amount, the engaging / disengaging means is operated. The driving force transmission hand Selectively engage and disengage with respect to the respective displacement means, die height adjustment device, characterized in that it comprises a control unit for driving and controlling the drive source. 2. The device according to claim 1, wherein the displacing means comprises a nut gear screwed to each tie bar, and the nut gear and the driving source are connected by a connecting gear which is a driving force transmitting means. Die height adjusting device. 3. The device according to claim 2, wherein the engaging / disengaging means displaces the connecting gear with respect to the nut gear,
A die height adjusting device composed of a cylinder for engaging and disengaging the die. 4. The die height adjusting device according to claim 1, wherein the detecting means is a load meter that detects a mold clamping force between a fixed mold and a movable mold in each tie bar.