JP2500142Y2 - Mold holding device for vertical injection molding machine - Google Patents

Description

[Detailed description of the device]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gripping device suitable for gripping an upper mold and separating it from a lower mold in a vertical injection molding apparatus.

[0002]

2. Description of the Related Art In a multifaceted vertical injection molding machine,
As shown in FIG. 9, a fixed platen (rotary table) 21 disposed beside the vertical injection molding machine is rotated to rotate the lower mold 22.
b at the injection position of the injection molding machine, and the other lower mold 22b whose cavity is filled with resin is moved to another rotation position together with the upper mold 22a by the injection molding machine to move the upper mold 22a. After being gripped by the four hydraulic clampers 23, they are lifted and separated from the lower mold 22b, and the molded product is taken out. Reference numeral 24 is an elevator which has hydraulic clampers 23 attached to the four corners thereof and is moved up and down by a hydraulic cylinder. The lower die 22b is detachably fixed to the stationary platen 21 by a hydraulic clamper 25. Each of the hydraulic clampers 23 and 25 is composed of a hydraulic cylinder and has a piston rod 23.
The flanges of the upper mold 22a or the lower mold 22b are locked by a and 25a to fix them to the lift plate 24 or the fixed plate 21.

In a conventional gripping device mainly composed of four hydraulic clampers 23, as shown in FIG. 10, the four hydraulic clampers 23 are connected to each other by one system of pipes 27a and 27b provided with an electromagnetic switching valve SOL. It is connected to a hydraulic pump 28. 9 and 10, the piston rods 23a and 25a of the hydraulic cylinder are used for the upper die 22a and the lower die 22.
Although the flange b is directly locked, there is also a hydraulic cylinder in which a pin is moved and locked via a connecting plate (JP-A-51-6128).

[0004]

In the above-mentioned conventional gripping device, the flow direction of the hydraulic oil is changed due to a failure of the electromagnetic switching valve SOL or a short circuit of the control line for controlling the operation of the electromagnetic switching valve SOL. If there is a case of sudden switching, there is a risk that the four hydraulic clampers 23 will malfunction at the same time and the upper die 22a that has been held until then will fall.

The present invention is to provide a mold holding device for a vertical injection molding device or the like which has a high reliability of operation without the risk of the mold dropping due to a failure of one piping system. To aim.

[0006]

In order to achieve the above object, the present invention provides a fixing plate for supporting a lower mold, and a first plate capable of holding one upper mold. An elevator board provided with a fluid pressure clamper group and a second fluid pressure clamper group, and the elevator board
An up / down means for moving up and down with respect to the fixed plate, and a first switching position
Gripping the first fluid pressure clamper group in
Also releases the first fluid pressure clamper group at the second switching position.
A first pipe having a first electromagnetic switching valve to be operated, which connects the first fluid pressure clamper group to a fluid pressure supply source, and a first switching position.
Gripping the second fluid pressure clamper group in
Also, release the second fluid pressure clamper group at the second switching position.
A second pipe having a second electromagnetic switching valve to be operated, which connects the second fluid pressure clamper group to a fluid pressure supply source, and the stationary plate.
On the lower die supported by
A party that outputs a signal when the upper die moves down
Lifting confirmation switch means and the above and below means
Is raised above the fixed plate above the specified height
To the second switching position of both solenoid switching valves.
The wiring cut switch means for disabling the switching of
The tightening pressure of the lower mold and the upper mold by the up-and-down means is the specified pressure
A pressure switch means for outputting a signal when the pressure exceeds
Both parting confirmation switch means and pressure switch means
If both signals are output simultaneously,
An ANDING device that enables switching of the valve to the second switching position described above.
It is configured to include a connecting means . Elevator is a vertical means
Outputs a signal when it is raised and reaches the upper limit
Equipped with raising switch means, parting confirmation switch hand
The number of steps and wiring cut switch means and pressure switch means are small.
At least one and both of them in the above-mentioned rising limit switch means
If a signal is output from one of the
Is preferably a structure as child having a self-diagnosis circuit to force
Yes.

[0007]

[Effect] Even if one fluid pressure clamper group that receives a fluid pressure supply through the one piping system malfunctions and malfunctions, the fluid pressure clamper groups of the other piping systems do not malfunction, and Continue to hold the mold. Therefore, the mold is prevented from falling and the safety is maintained. Wiring cut switch means
The lifting mechanism raises or lowers the lift plate from the fixed plate to a predetermined height or more.
When the valve is raised, the contact is opened and the second
Disables switching to the switching position. And gate
Means are parting confirmation switch means and pressure switch
If signals are output from both means simultaneously, both electromagnetic
It is possible to switch the switching valve to the second switching position.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described with reference to FIGS. In the figure, reference numerals 1 and 2 are hydraulic clampers. The two hydraulic clampers 1 and 1 are arranged in one diagonal position, and the other two hydraulic clampers 2 and 2 are arranged in other diagonal positions, respectively, and are fixed to the elevator 24 as in the conventional case. Each of the hydraulic clampers 1 and 2 has piston rods 1a and 2a for locking the flange of the upper die 22a, and two hydraulic clampers 1 and 1 (fluid pressure clamper group A) in one diagonal position and others. 2 hydraulic clampers in the diagonal position of
The 2 (fluid pressure clamper group B) has its locking force, strength, etc. set so that the upper mold 22a can be gripped independently.

The two hydraulic clampers 1, 1 in one diagonal position are connected to the hydraulic pump (fluid pressure supply source) 4 by the pipes 3a, 3b provided with the electromagnetic switching valve SOL1. The two hydraulic clampers 2 and 2 located in the diagonal position of are the pipes 5a provided with the electromagnetic switching valve SOL2,
It is connected to the hydraulic pump 4 by 5b. Although two hydraulic pumps 4 and 4 are used in FIG. 1, the hydraulic pump 4 may be one. Hydraulic clampers 1 and 2
When the electromagnetic switching valves SOL1 and SOL2 are set to the neutral position, the springs (not shown) cause the piston rods 1a and 2a to project.

Each of the hydraulic clampers 1 and 2 has one release (release operation) confirmation limit switch LS1, LS3.
LS5, LS7 and one gripping (gripping operation) confirmation limit switch LS2, LS4, LS6, LS8 are attached respectively. Further, the hydraulic cylinder 8 is provided with a parting confirmation pressure switch (pressure switch means) PS.

The elevating plate 24 is moved up and down with respect to the fixed plate 21 by a hydraulic cylinder (up / down means) 8 attached to the support plate 7. Dogs 9, 10, and 11 are provided on the elevator board 24, and a fixed board 21 includes a parting confirmation limit switch LS14 and solenoid wiring cut limit switches LS12 and LS13 (two LS12 and LS13 are shown in FIGS. 2 to 6). The upper limit switch LS11 is provided on the support plate 7.

The limit switches LS1 to LS8,
The LS 11 to LS 14 and the pressure switch PS are connected to the control device 13 via the input circuit 12. And each grip confirmation limit switch LS2, LS4, LS
When the hydraulic clampers 1 and 2 have finished extending the piston rods 1a and 2a, 6 and LS8 are turned on and output a grip confirmation signal to the control device 13 via the input circuit 12. In addition, each release confirmation limit switch LS1, LS3, LS
When the hydraulic clampers 1 and 2 contract the piston rods 1a and 2a, the LS7 and LS7 turn on and output a release confirmation signal.

The ascending limit switch LS11 is pushed by the dog 11 and outputs a signal when the elevator board 24 is raised by the hydraulic cylinder 8 and reaches the ascending limit. In addition, each solenoid wiring cut limit switch LS12, LS
Reference numeral 13 denotes contacts LS12S, L while the elevator board 24 is descending below a predetermined height position and is being pushed by the dog 10.
When S13S is closed and the elevator board 24 is lifted to a predetermined height or higher and the dog 10 is separated, the contacts LS12S and LS13S are opened. The contacts LS12S, LS13S are connected in series to the solenoids b, b of the electromagnetic switching valves SOL1, SOL2. Therefore, when the dog 10 is away from the solenoid wiring cut limit switches LS12, LS13, the solenoids b of the electromagnetic switching valves SOL1, SOL2 are not excited to reduce the piston rods 1a, 2a of the hydraulic clampers 1, 2. , Is kept safe.
The rising limit switch LS11 and dog 11 are
It constitutes the rising limit switch means, and also the solenoid wiring
The limit switches LS12 and LS13 and the dog 10 are
It constitutes a line cut switch means.

Parting confirmation limit switch LS1
4, when the upper mold 22a is lowered onto the lower mold 22b,
It is pressed by the dog 9 and outputs a confirmation signal. Further, in the parting confirmation pressure switch PS, the hydraulic cylinder 8 extends and the upper die 22a is placed on the lower die 22b, and the tightening pressure thereof, that is, the pressure on the head side of the hydraulic cylinder 8 is a predetermined value (Fig. When it is 100 kg / cm ² ) or more, it turns on and outputs a signal. Each solenoid switching valve SOL1, SOL
Each of the two solenoids a and b is connected to the control device 13 via the output circuit 14. The parting confirmation limit
Switch LS14 and dog 9 are parting confirmation switches.
Constitutes a switch means.

In the control circuit of the control device 13, as shown in FIG. 8, each of the limit switches LS1 to LS8, LS11.
A self-diagnosis circuit for LS14 and the pressure switch PS is provided. That is, AND gate (self-diagnosis times
Road) AND1, together with lighting the lamp R1 of the display unit when the ascent limit limit switch LS11 and the solenoid wire never turned on simultaneously in the normal cut limit switch LS12 which (LS13) is turned on at the same time, the machine stops Output a command.

An AND gate (self-diagnosis circuit) AN
Similarly to the above, D2 turns on the lamp R2 and outputs a machine stop command when the ascending limit switch LS11 and the parting confirmation limit switch LS14 are simultaneously turned on. AND gate (self-diagnosis circuit)
When the ascending limit switch LS11 and the parting confirmation pressure switch PS are simultaneously turned on, the AND3 turns on the lamp R3 and outputs a machine stop command.

Further, the AND gate AND4 holds the grip confirmation limit switches LS2, LS when the solenoid wiring cut limit switch LS12 (LS13) is off.
8 (LS4, LS6) are off at the same time, lamp R4
Is turned on and a machine stop command is output. And Gate A
ND5, when the clamp release command is ON and the solenoid wiring cut limit switches LS12 and LS13 are ON,
Release confirmation limit switches LS1, LS7 (LS3, L
If S5) is off at the same time, the lamp R5 is turned on and a machine stop command is output.

Also, an exclusive NOR gate EX-
NOR is a pair of grip confirmation limit switches L
When S2, LS4, LS6, LS8 and the release confirmation limit switches LS1, LS3, LS5, LS7 are simultaneously turned on or off (time lag is required), the lamp R6 is turned on and a machine stop command is output. AND gate (AND gate means) AND6 enables the output of the clamp release command when the parting confirmation limit switch LS14 and the parting confirmation pressure switch PS are simultaneously turned on.

Next, the operation of the upper die holding device in the vertical injection molding apparatus of the present invention constructed as above will be described. FIG. 2 shows that the solenoids a, a of the electromagnetic switching valves SOL1, SOL2 are excited and the hydraulic clampers 1.1, 2, 2.
2 shows the lifted state of the lift plate 24 holding the upper die 22a in this state. In this state, the solenoid wiring cut limit switches LS12, LS13 are released from the pressing force of the dog 10 and their contacts LS12S, LS13S are opened. . Therefore, the solenoid b of each electromagnetic switching valve SOL1, SOL2 cannot be excited, and each hydraulic clamper 1.2
The upper die 22a is normally held by the piston rods 1a and 2a.

In the above-mentioned gripping state, one solenoid switching valve SOL1 (or SO
Even if the solenoid b of L2) is excited and the piston rod of the hydraulic clamper 1, 1 (or 2, 2) related to the solenoid switching valve is arbitrarily reduced, another normal solenoid switching valve Since the hydraulic clampers 2, 2 (or 1, 1) of SOL2 (or SOL1) continue to grip the upper mold 22a with their piston rods, a fall accident of the upper mold 22a is prevented.

When the hydraulic cylinder 8 is extended from the state shown in FIG. 2, the lift plate 24 is lowered. At this time, the dog 11 is separated from the ascent limit switch LS11, and then the solenoid wiring cut switches LS12 and LS13 are pushed by the dog 10 (FIG. 3). Finally, the parting confirmation limit switch LS14 is pushed by the dog 9, and the parting confirmation pressure switch PS is turned on (FIG. 4).

When the upper die 22a is removed from the lift plate 24, the electromagnetic switching valves SOL1 and SOL in the state shown in FIG.
2 solenoids b, b are excited, and hydraulic clampers 1,
Upper die 22 by reducing the piston rods 1a, 2a
Release the grip of a. In FIG. 5, the upper die 22a is removed and the elevator board 2
4 shows a state in which 4 is slightly raised, and FIG. In the case of FIG. 5, the dog 10 is the solenoid wiring cut limit switches LS12, LS1.
Since the piston rods 1a and 2a of the hydraulic clampers 1 and 2 are still contracted because 3 is pressed, in FIG. 6, the solenoid wiring cut limit switch LS is shown.
12, LS13 is released from the pressure applied by the dog 10, and contacts L
Since S12S and LS13S are open, the piston rods 1a and 2a are projected outward by the action of the springs attached to the hydraulic clampers 1 and 2.

According to the above embodiment, since the two fluid pressure clamper groups A and B are operated via independent piping systems, even if one piping system fails, the other piping systems will operate. It is safe because the system can hold the dies, and the dies 22a and 22b are controlled by the parting confirmation pressure switch PS, the parting confirmation limit switch LS14, and the solenoid wiring cut switches LS12 and LS13.
Since the hydraulic clampers 1 and 2 do not release the grip of the upper mold 22a at the positions where the upper mold 22a is not matched by the parting, the upper mold 22a is prevented from dropping unintentionally during its lifting operation. It is also safe in this respect.

The hydraulic clampers 1 and 2 can be replaced by pneumatic clampers using pneumatic cylinders. The hydraulic clampers 1 and 2 are connected to the upper mold 2 by piston rods 1a and 2a.
Although it is configured to directly grip the 2a, the upper die 22a may be gripped by another attachment member. Furthermore, the fluid pressure clamper groups A and B of the embodiment shown in FIG.
Each has two hydraulic clampers 1, 1, 2 and 2, but the number of clampers can be three or more. In this case, the arrangement is arbitrary as long as each of the fluid pressure clamper groups A and B can independently hold one upper die 22a. Further, in the illustrated embodiment, the number of the fluid pressure clamper group is two, but it may be three or more.

[0025]

As described above, the mold holding device of the vertical injection molding apparatus of the present invention supports the lower mold.
Fixed plate and first that can hold one upper mold
An elevator including a fluid pressure clamper group and a second fluid pressure clamper group, and an upper and lower plate for moving the elevator up and down with respect to the fixed plate.
The lower means and the first fluid pressure clan in the first switching position.
The group of grippers is operated to grip, and the first flow is performed at the second switching position.
A first pipe having a first electromagnetic switching valve for releasing the body pressure clamper group and connecting the first fluid pressure clamper group to a fluid pressure supply source; and the second fluid pressure clamp in the first switching position.
The group of grippers is operated to grip, and the second flow is performed at the second switching position.
Above the lower die supported by the stationary plate, a second pipe provided with a second electromagnetic switching valve for releasing the body pressure clamper group and connecting the second fluid pressure clamper group to a fluid pressure supply source ;
If the upper die is lowered due to the lowering of the elevator by the lower means,
Parting confirmation switch means for outputting
By the lower means, the lift plate is above a certain height from the fixed plate.
Open the contacts when the valve is raised to
Wiring cut to disable switching to the second switching position
The switch means and the lower die and upper die by the above-mentioned up and down means
Pressure to output a signal when the tightening pressure exceeds the specified pressure
Switch means and the parting confirmation switch means
If signals are output simultaneously from both pressure switch means,
The two solenoid switching valves to the second switching position.
Since the AND gate means for enabling the above is provided, even if one piping system fails, the mold being gripped does not drop or fall down, which is safe. Ma
Parting confirmation switch means and pressure switch means
Only when both signals are output simultaneously
It is possible to switch the switching valve to the second switching position,
Depending on the steps, the elevator board is lifted above the fixed height from the fixed board.
Then, the operation of the wiring cut switch means
It is impossible to switch the electromagnetic switching valve to the second switching position.
It is possible to prevent malfunction due to short circuit of wiring.
It

[0026] The lift board is lifted by the vertical movement means
Equipped with rising limit switch means that outputs a signal when the
, The parting confirmation switch means and the wiring cut switch
And at least one of a pressure switch means and a pressure switch means.
Signals from both the boost switch means and to them simultaneously
Self-diagnosis circuit that outputs a machine stop command when
When configured, each switch means
Self-diagnosis whether it is abnormal or not, and if abnormal, stop the machine
Therefore, excessive operation will not increase the failure.
Yes.

[Brief description of drawings]

FIG. 1 is a hydraulic circuit diagram showing an embodiment of a mold holding device in a vertical injection molding device or the like of the present invention.

FIG. 2 is a front view showing a lifted state of an elevator including the gripping device.

FIG. 3 is a front view showing a state in which the elevator board is being lowered.

FIG. 4 is a front view showing a lowered state of the elevator board.

FIG. 5 is a front view showing a state in which the upper mold is removed and the elevator board is slightly raised.

FIG. 6 is a front view showing a lifted state of the lift plate without the upper mold.

FIG. 7 is an electric circuit diagram of various limit switches and the like.

FIG. 8 is a self-diagnosis circuit diagram of various limit switches and the like.

FIG. 9 is a partially cutaway front view showing a gripping state of an upper mold by a conventional gripping device.

FIG. 10 is a hydraulic circuit diagram of a conventional gripping device.

[Explanation of symbols]

1, 2 Hydraulic Clamper 1a, 2a Piston Rod 3a, 3b Piping 4 Hydraulic Pump (Fluid Pressure Supply) 5a, 5b Piping 8 Hydraulic Cylinder (Upper and Lower Means) 21 Fixed Plate 22a Upper Mold 22b Lower Mold 24 Lifting Plate A, B Fluid pressure clamper group LS11 Lift limit switch LS12, LS13 Solenoid wiring cut limit switch
Switch LS14 Parting confirmation limit switch LS12S, LS13S contact PS Parting confirmation pressure switch AND1, AND2, AND3 AND gate (self-diagnosis
Disconnection circuit) AND6 AND gate (AND gate means) SOL1, SOL2 Solenoid switching valve

Claims (2)

(57) [Scope of utility model registration request] And 1. A stationary platen for supporting a lower mold, and the lifting plate having a first fluid pressure clamper group and the second fluid pressure clamper group can grip one of the upper mold, the elevator Board up
An up / down means for moving up and down with respect to the fixed plate, and a first switching position
In the above step, the first fluid pressure clamper group is gripped and operated.
Release the first fluid pressure clamper group at the second switching position.
A first pipe having a first electromagnetic switching valve for moving the first fluid pressure clamper group connected to a fluid pressure supply source; and a first switching position
In step 2, the second fluid pressure clamper group is gripped and operated.
Release the second fluid pressure clamper group at the second switching position.
A second pipe having a second electromagnetic switching valve for moving the second fluid pressure clamper group connected to a fluid pressure supply source; and the stationary plate.
On the supported lower mold, lowering the elevator board by the above-mentioned lifting means.
A party that outputs a signal when the upper mold descends below
The elevator board can be
When raised above the fixed plate above the specified height
Open the contact to move the solenoid valves to the second switching position.
Wiring cut switch means that disables switching, and above
The clamping pressure of the lower mold and the upper mold by the lower means exceeds the specified pressure.
Pressure switch means for outputting a signal when
Both the starting confirmation switch means and the pressure switch means
When the signals are output simultaneously from both solenoid switching valves
Which enables the switching of the
Mold gripping device in vertical injection molding machine or the like, characterized by comprising a preparative means. (2) The elevator board is lifted by the vertical movement means
Ascending limit switch means that outputs a signal when the limit is reached
Equipped, parting confirmation switch means and wiring cut switch
Switch means and / or pressure switch means, and
Ascending limit switch means and signal from both of them simultaneously
Self-diagnosis circuit that outputs a machine stop command when it is output
The vertical injection according to claim 1, characterized in that
Mold holding device for molding equipment.